TY  - CONF
AU  - Veljović, Đorđe
AU  - Janaćković, Đorđe
AU  - Petrović, Rada
AU  - Radovanović, Željko
AU  - Ugrinović, Vukašin
AU  - Matić, Tamara
AU  - Milivojević, Marija
PY  - 2024
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/7439
AB  - Bioactive  materials  for  the repairand  regeneration  of human bone  tissue,  as  well  as  for  the restoration  of  teeth,  are  the focus of  numerous  studies  in  the  field  of  biomaterials.Orthopaedic  surgeons  anticipate that  bioactive materialshave  the  potential  to  facilitate  the  formation  of  new  apatite-like  crystals  upon  contact  with body fluids, promoting the development of new bone tissue under in vivoconditions. On the other hand, dentists expect that bioactive  materials  have  the  potential  for  remineralization  of  partially  demineralized  enamel  and  dentin. In  the preceding years, the Bioceramic Materials Group, founded within the Department of Inorganic Chemical Technology at the  Faculty  of  Technology  and  Metallurgy,  University  of  Belgrade (FTM-UB),  conducted  extensive  research  on  the advancement of bioactive and biocompatible materials with adequate mechanical properties, designed for applicationin dentistry, orthopaedics, maxillofacial surgery, and also bone tissue engineering(BTE).
PB  - Savez hemijskih inženjera Srbije
C3  - Hemijska industrija
T1  - The current trend in innovative bioactive materials for dental and orthopedic applications
IS  - 1S
SP  - 37
VL  - 78
UR  - https://hdl.handle.net/21.15107/rcub_technorep_7439
ER  - 

@conference{
author = "Veljović, Đorđe and Janaćković, Đorđe and Petrović, Rada and Radovanović, Željko and Ugrinović, Vukašin and Matić, Tamara and Milivojević, Marija",
year = "2024",
abstract = "Bioactive  materials  for  the repairand  regeneration  of human bone  tissue,  as  well  as  for  the restoration  of  teeth,  are  the focus of  numerous  studies  in  the  field  of  biomaterials.Orthopaedic  surgeons  anticipate that  bioactive materialshave  the  potential  to  facilitate  the  formation  of  new  apatite-like  crystals  upon  contact  with body fluids, promoting the development of new bone tissue under in vivoconditions. On the other hand, dentists expect that bioactive  materials  have  the  potential  for  remineralization  of  partially  demineralized  enamel  and  dentin. In  the preceding years, the Bioceramic Materials Group, founded within the Department of Inorganic Chemical Technology at the  Faculty  of  Technology  and  Metallurgy,  University  of  Belgrade (FTM-UB),  conducted  extensive  research  on  the advancement of bioactive and biocompatible materials with adequate mechanical properties, designed for applicationin dentistry, orthopaedics, maxillofacial surgery, and also bone tissue engineering(BTE).",
publisher = "Savez hemijskih inženjera Srbije",
journal = "Hemijska industrija",
title = "The current trend in innovative bioactive materials for dental and orthopedic applications",
number = "1S",
pages = "37",
volume = "78",
url = "https://hdl.handle.net/21.15107/rcub_technorep_7439"
}

Veljović, Đ., Janaćković, Đ., Petrović, R., Radovanović, Ž., Ugrinović, V., Matić, T.,& Milivojević, M.. (2024). The current trend in innovative bioactive materials for dental and orthopedic applications. in Hemijska industrija
Savez hemijskih inženjera Srbije., 78(1S), 37.
https://hdl.handle.net/21.15107/rcub_technorep_7439

Veljović Đ, Janaćković Đ, Petrović R, Radovanović Ž, Ugrinović V, Matić T, Milivojević M. The current trend in innovative bioactive materials for dental and orthopedic applications. in Hemijska industrija. 2024;78(1S):37.
https://hdl.handle.net/21.15107/rcub_technorep_7439 .

Veljović, Đorđe, Janaćković, Đorđe, Petrović, Rada, Radovanović, Željko, Ugrinović, Vukašin, Matić, Tamara, Milivojević, Marija, "The current trend in innovative bioactive materials for dental and orthopedic applications" in Hemijska industrija, 78, no. 1S (2024):37,
https://hdl.handle.net/21.15107/rcub_technorep_7439 .

TY  - CONF
AU  - Ugrinović, Vukašin
AU  - Marković, Maja
AU  - Petrović, Predrag
AU  - Veljović, Đorđe
PY  - 2024
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/7393
AB  - INTRODUCTION: Hydrogels,  characterized  by  their  three-dimensional  hydrophilic  polymer  networks  capable  of retaining substantial amounts of water or biological fluids, hold significant promise for biomedical and pharmaceutical applications.  While  numerous  polymers  have  been  explored  for  hydrogel  development,  those  derived  from  natural sources  possess  inherent  advantages  due  to  their  abundance,  affordability,  biocompatibility,  and  biodegradability. Gelatin, a widely used natural polymer in biomedicine, standsout for its cost-effectiveness, compatibility with biological systems,  and  degradability.  Hydroxypropyl  methylcellulose  (HPMC),  a  cellulose  derivative,  exhibits  hydrophilicity, biodegradability,  and  biocompatibility.  However,  natural  polymer-based  hydrogels  often  exhibit  low  mechanical strength  and  solubility  in  physiological  conditions,  necessitating  innovative  cross-linking  strategies  to  enhance  their functionality. Citric acid (CA) emerges as a promising crosslinking agent owing to its affordability andnon-toxic nature.EXPERIMENTAL:HPMC-G hydrogels were synthesized by dissolving gelatin (0.05 g) and HPMC (0.1 g) with specified amounts of CA and sodium hypophosphitein 1 ml of distilled water in a reaction vessel. The mixture was homogenized, poured into a Teflon mold, and frozen at -20°C for 24 hours. After lyophilization, the hydrogels underwent crosslinking at 160°C for 7 minutes. By varying the CA content from 0%to 40% (w/w) while maintaining constant temperature and time, the optimal CA/HPMC ratio was determined. Subsequently, various heat treatments (140–180°C, 3-12 minutes) were applied to explore the optimal curing conditions.RESULTS AND DISCUSSION:The investigation elucidates how the CA/HPMC ratio and curing conditions impact the physicochemical and mechanical propertiesof HPMC-G hydrogels. Swelling tests and compressive mechanical property evaluations reveal that the incorporation of citric acid, along with increases in curing temperature and time, enhances compressive  modulus  and  degradation  stability  while  reducing  equilibrium  swelling.  Scanning  electron  microscopyanalysis reveals a highly porous microstructure in the resulting hydrogels, while differential scanning calorimetrycurves indicate the formation of strong interactions between gelatin and HPMC.CONCLUSIONS:The utilization of these materials notonly contributes to environmental conservation efforts but also drives the advancement of eco-friendly technology, aligning with the principles of the circular economy. Moreover, it offers promising avenues for innovative solutions in potential biomedicalapplications.
PB  - Savez hemijskih inženjera Srbije
C3  - Hemijska industrija - Supplementary Issue - ExcellMater Conference 2024 Abstracts
T1  - Citric acid-crosslinked gelatin/hydroxypropyl methylcellulose hydrogels for biomedical applications
IS  - 1S
SP  - 29
VL  - 78
UR  - https://hdl.handle.net/21.15107/rcub_technorep_7393
ER  - 

@conference{
author = "Ugrinović, Vukašin and Marković, Maja and Petrović, Predrag and Veljović, Đorđe",
year = "2024",
abstract = "INTRODUCTION: Hydrogels,  characterized  by  their  three-dimensional  hydrophilic  polymer  networks  capable  of retaining substantial amounts of water or biological fluids, hold significant promise for biomedical and pharmaceutical applications.  While  numerous  polymers  have  been  explored  for  hydrogel  development,  those  derived  from  natural sources  possess  inherent  advantages  due  to  their  abundance,  affordability,  biocompatibility,  and  biodegradability. Gelatin, a widely used natural polymer in biomedicine, standsout for its cost-effectiveness, compatibility with biological systems,  and  degradability.  Hydroxypropyl  methylcellulose  (HPMC),  a  cellulose  derivative,  exhibits  hydrophilicity, biodegradability,  and  biocompatibility.  However,  natural  polymer-based  hydrogels  often  exhibit  low  mechanical strength  and  solubility  in  physiological  conditions,  necessitating  innovative  cross-linking  strategies  to  enhance  their functionality. Citric acid (CA) emerges as a promising crosslinking agent owing to its affordability andnon-toxic nature.EXPERIMENTAL:HPMC-G hydrogels were synthesized by dissolving gelatin (0.05 g) and HPMC (0.1 g) with specified amounts of CA and sodium hypophosphitein 1 ml of distilled water in a reaction vessel. The mixture was homogenized, poured into a Teflon mold, and frozen at -20°C for 24 hours. After lyophilization, the hydrogels underwent crosslinking at 160°C for 7 minutes. By varying the CA content from 0%to 40% (w/w) while maintaining constant temperature and time, the optimal CA/HPMC ratio was determined. Subsequently, various heat treatments (140–180°C, 3-12 minutes) were applied to explore the optimal curing conditions.RESULTS AND DISCUSSION:The investigation elucidates how the CA/HPMC ratio and curing conditions impact the physicochemical and mechanical propertiesof HPMC-G hydrogels. Swelling tests and compressive mechanical property evaluations reveal that the incorporation of citric acid, along with increases in curing temperature and time, enhances compressive  modulus  and  degradation  stability  while  reducing  equilibrium  swelling.  Scanning  electron  microscopyanalysis reveals a highly porous microstructure in the resulting hydrogels, while differential scanning calorimetrycurves indicate the formation of strong interactions between gelatin and HPMC.CONCLUSIONS:The utilization of these materials notonly contributes to environmental conservation efforts but also drives the advancement of eco-friendly technology, aligning with the principles of the circular economy. Moreover, it offers promising avenues for innovative solutions in potential biomedicalapplications.",
publisher = "Savez hemijskih inženjera Srbije",
journal = "Hemijska industrija - Supplementary Issue - ExcellMater Conference 2024 Abstracts",
title = "Citric acid-crosslinked gelatin/hydroxypropyl methylcellulose hydrogels for biomedical applications",
number = "1S",
pages = "29",
volume = "78",
url = "https://hdl.handle.net/21.15107/rcub_technorep_7393"
}

Ugrinović, V., Marković, M., Petrović, P.,& Veljović, Đ.. (2024). Citric acid-crosslinked gelatin/hydroxypropyl methylcellulose hydrogels for biomedical applications. in Hemijska industrija - Supplementary Issue - ExcellMater Conference 2024 Abstracts
Savez hemijskih inženjera Srbije., 78(1S), 29.
https://hdl.handle.net/21.15107/rcub_technorep_7393

Ugrinović V, Marković M, Petrović P, Veljović Đ. Citric acid-crosslinked gelatin/hydroxypropyl methylcellulose hydrogels for biomedical applications. in Hemijska industrija - Supplementary Issue - ExcellMater Conference 2024 Abstracts. 2024;78(1S):29.
https://hdl.handle.net/21.15107/rcub_technorep_7393 .

Ugrinović, Vukašin, Marković, Maja, Petrović, Predrag, Veljović, Đorđe, "Citric acid-crosslinked gelatin/hydroxypropyl methylcellulose hydrogels for biomedical applications" in Hemijska industrija - Supplementary Issue - ExcellMater Conference 2024 Abstracts, 78, no. 1S (2024):29,
https://hdl.handle.net/21.15107/rcub_technorep_7393 .

TY  - CHAP
AU  - Mihajlović, Dragana
AU  - Rakin, Marko
AU  - Hohenwarter, Anton
AU  - Veljović, Đorđe
AU  - Kojić, Vesna
AU  - Đokić, Veljko
PY  - 2024
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/7147
AB  - Primary implant stability after implantation is in relation with its good mechanical contact with the touching tissue. Adequate integration of the implant with the bone tissue is necessary to provide safety and efficiency of the implant over its life. Generally, two surface properties are the most important facts for tissue response to the implant: the surface topography and chemical composition. Compared to a smooth implant surface, a controlled rough surface provides more surface area for integration with the surrounding tissues and allows successful implant ingrowth into the tissues. It was found that the nanostructured modification of the titanium surface on the level of nano-sized pores influences the adhesion, spreading and growing of osteoblastic cells. There are many methods for nanostructure modification of biomedical alloy surfaces, but one of the common techniques is electrochemical anodization (anodic oxidation). Electrochemical anodization is a method that leads to the creation of a nanotubular oxide film on the material surface. The advantage of anodic oxidation is the possibility of controlling the nanostructured morphology of the surface and dimensions of nanotubes, such as diameter, length, wall thickness and shape of nanotubes through variation of the solution, pH value, potential or duration of anodic oxidation. 
Surface modification of Ti-13Nb-13Zr alloy in a coarse-grained (as received) and ultrafine-grained state induced by high pressure torsion was conducted using an electrochemical anodization process in a 1 M H3PO4 + NaF electrolyte, for 30, 60, 90 and 120 minutes. Scanning electron microscopy (SEM) was used to analyze the morphology, while atomic force microscopy (AFM) was used to characterize the topography of the modified surface. The results showed that a homogenous nanotubular oxide film consisting of nanotubes could be obtained using the electrochemical anodization treatment, while the roughness of the nanostructured surface increased compared to the bare surface. The aim of the studies given in this chapter is to examine the morphology of the nanostructured surface and estimate in vitro biocompatibility of the above-mentioned titanium alloy after the creation of the nanotubular oxide film. In vitro examinations were performed on mouse fibroblast (L929) and human fibroblast (MRC-5) cell lines. The results showed that the nanotubular oxide film obtained on the coarse-grained Ti-13Nb-13Zr alloy (CG TNZ) and the ultrafine-grained Ti-13Nb-13Zr alloy (UFG TNZ) increased the fractions of surviving cells compared to their counterpart alloy, while the cells had better spreading and adhesion on the nanostructured and bare surfaces of the UFG titanium alloy.
PB  - Hoboken : John Wiley & Sons
PB  - Beverly : Scrivener Publishing LLC
T2  - Mechanical Engineering in Biomedical Application: Bio-3D Printing, Biofluid Mechanics, Implant Design, Biomaterials, Computational Biomechanics, Tissue Mechanics
T1  - The Effect of the Nanostructured Surface Modification on the Morphology and Biocompatibility of Ultrafine-Grained Titanium Alloy for Medical Application
EP  - 150
SP  - 121
DO  - 10.1002/9781394175109.ch5
UR  - https://hdl.handle.net/21.15107/rcub_technorep_7147
ER  - 

@inbook{
author = "Mihajlović, Dragana and Rakin, Marko and Hohenwarter, Anton and Veljović, Đorđe and Kojić, Vesna and Đokić, Veljko",
year = "2024",
abstract = "Primary implant stability after implantation is in relation with its good mechanical contact with the touching tissue. Adequate integration of the implant with the bone tissue is necessary to provide safety and efficiency of the implant over its life. Generally, two surface properties are the most important facts for tissue response to the implant: the surface topography and chemical composition. Compared to a smooth implant surface, a controlled rough surface provides more surface area for integration with the surrounding tissues and allows successful implant ingrowth into the tissues. It was found that the nanostructured modification of the titanium surface on the level of nano-sized pores influences the adhesion, spreading and growing of osteoblastic cells. There are many methods for nanostructure modification of biomedical alloy surfaces, but one of the common techniques is electrochemical anodization (anodic oxidation). Electrochemical anodization is a method that leads to the creation of a nanotubular oxide film on the material surface. The advantage of anodic oxidation is the possibility of controlling the nanostructured morphology of the surface and dimensions of nanotubes, such as diameter, length, wall thickness and shape of nanotubes through variation of the solution, pH value, potential or duration of anodic oxidation. 
Surface modification of Ti-13Nb-13Zr alloy in a coarse-grained (as received) and ultrafine-grained state induced by high pressure torsion was conducted using an electrochemical anodization process in a 1 M H3PO4 + NaF electrolyte, for 30, 60, 90 and 120 minutes. Scanning electron microscopy (SEM) was used to analyze the morphology, while atomic force microscopy (AFM) was used to characterize the topography of the modified surface. The results showed that a homogenous nanotubular oxide film consisting of nanotubes could be obtained using the electrochemical anodization treatment, while the roughness of the nanostructured surface increased compared to the bare surface. The aim of the studies given in this chapter is to examine the morphology of the nanostructured surface and estimate in vitro biocompatibility of the above-mentioned titanium alloy after the creation of the nanotubular oxide film. In vitro examinations were performed on mouse fibroblast (L929) and human fibroblast (MRC-5) cell lines. The results showed that the nanotubular oxide film obtained on the coarse-grained Ti-13Nb-13Zr alloy (CG TNZ) and the ultrafine-grained Ti-13Nb-13Zr alloy (UFG TNZ) increased the fractions of surviving cells compared to their counterpart alloy, while the cells had better spreading and adhesion on the nanostructured and bare surfaces of the UFG titanium alloy.",
publisher = "Hoboken : John Wiley & Sons, Beverly : Scrivener Publishing LLC",
journal = "Mechanical Engineering in Biomedical Application: Bio-3D Printing, Biofluid Mechanics, Implant Design, Biomaterials, Computational Biomechanics, Tissue Mechanics",
booktitle = "The Effect of the Nanostructured Surface Modification on the Morphology and Biocompatibility of Ultrafine-Grained Titanium Alloy for Medical Application",
pages = "150-121",
doi = "10.1002/9781394175109.ch5",
url = "https://hdl.handle.net/21.15107/rcub_technorep_7147"
}

Mihajlović, D., Rakin, M., Hohenwarter, A., Veljović, Đ., Kojić, V.,& Đokić, V.. (2024). The Effect of the Nanostructured Surface Modification on the Morphology and Biocompatibility of Ultrafine-Grained Titanium Alloy for Medical Application. in Mechanical Engineering in Biomedical Application: Bio-3D Printing, Biofluid Mechanics, Implant Design, Biomaterials, Computational Biomechanics, Tissue Mechanics
Hoboken : John Wiley & Sons., 121-150.
https://doi.org/10.1002/9781394175109.ch5
https://hdl.handle.net/21.15107/rcub_technorep_7147

Mihajlović D, Rakin M, Hohenwarter A, Veljović Đ, Kojić V, Đokić V. The Effect of the Nanostructured Surface Modification on the Morphology and Biocompatibility of Ultrafine-Grained Titanium Alloy for Medical Application. in Mechanical Engineering in Biomedical Application: Bio-3D Printing, Biofluid Mechanics, Implant Design, Biomaterials, Computational Biomechanics, Tissue Mechanics. 2024;:121-150.
doi:10.1002/9781394175109.ch5
https://hdl.handle.net/21.15107/rcub_technorep_7147 .

Mihajlović, Dragana, Rakin, Marko, Hohenwarter, Anton, Veljović, Đorđe, Kojić, Vesna, Đokić, Veljko, "The Effect of the Nanostructured Surface Modification on the Morphology and Biocompatibility of Ultrafine-Grained Titanium Alloy for Medical Application" in Mechanical Engineering in Biomedical Application: Bio-3D Printing, Biofluid Mechanics, Implant Design, Biomaterials, Computational Biomechanics, Tissue Mechanics (2024):121-150,
https://doi.org/10.1002/9781394175109.ch5 .,
https://hdl.handle.net/21.15107/rcub_technorep_7147 .

TY  - JOUR
AU  - Petrović, Rada
AU  - Lazarević, Slavica
AU  - Janković-Častvan, Ivona
AU  - Matić, Tamara
AU  - Milivojević, Marko
AU  - Milošević, Dragana
AU  - Veljović, Đorđe
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5263
AB  - Kaolinite/illite (KUb) and sepiolite (SEP) clays were used to study Cr(III) adsorption removal from aqueous solutions so that they could be utilized after saturation for ceramic manufacturing. SEP had a larger specific surface area and a higher PZC than KUb. The removal of Cr(III) was evaluated using a batch equilibration procedure at pHi = 4 and pHi = 6. Fast removal kinetics were observed for both clays. Maximum removal capacity was determined by changing the concentration of Cr(III) while keeping the concentration of clay constant and by altering the amount of clay while keeping the concentration of Cr(III) constant. In all situations, SEP had greater capacity than KUb, and capacity was greater for both clays at higher pHi. Not only did the pHi impact the removal capacity and efficiency, but so did the pH during adsorption and the initial concentration of Cr(III). Because of the higher PZC, the pHf for SEP was higher for the same pHi. The higher the pH and Cr(III) concentration, the higher the probability of Cr(OH)3 precipitation and the higher the removal capacity. Dried saturated clays were uniaxially pressed and sintered at 1000 °C for 2 h. The densities of the sintered materials were nearly identical to those of pure clay-based materials, but the compressive strengths were higher, which is significant for the use of saturated clays as raw materials in ceramic manufacturing. Leaching of Cr from SEP-based material was significantly higher than from KUb-based material probably due to the presence of CaCO3 in the SEP.
PB  - Elsevier
T2  - Applied  Clay Sciences
T1  - Removal of trivalent chromium from aqueous solutions by natural clays: Valorization of saturated adsorbents as raw materials in ceramic manufacturing
SP  - 106747
VL  - 231
DO  - 10.1016/j.clay.2022.106747
ER  - 

@article{
author = "Petrović, Rada and Lazarević, Slavica and Janković-Častvan, Ivona and Matić, Tamara and Milivojević, Marko and Milošević, Dragana and Veljović, Đorđe",
year = "2023",
abstract = "Kaolinite/illite (KUb) and sepiolite (SEP) clays were used to study Cr(III) adsorption removal from aqueous solutions so that they could be utilized after saturation for ceramic manufacturing. SEP had a larger specific surface area and a higher PZC than KUb. The removal of Cr(III) was evaluated using a batch equilibration procedure at pHi = 4 and pHi = 6. Fast removal kinetics were observed for both clays. Maximum removal capacity was determined by changing the concentration of Cr(III) while keeping the concentration of clay constant and by altering the amount of clay while keeping the concentration of Cr(III) constant. In all situations, SEP had greater capacity than KUb, and capacity was greater for both clays at higher pHi. Not only did the pHi impact the removal capacity and efficiency, but so did the pH during adsorption and the initial concentration of Cr(III). Because of the higher PZC, the pHf for SEP was higher for the same pHi. The higher the pH and Cr(III) concentration, the higher the probability of Cr(OH)3 precipitation and the higher the removal capacity. Dried saturated clays were uniaxially pressed and sintered at 1000 °C for 2 h. The densities of the sintered materials were nearly identical to those of pure clay-based materials, but the compressive strengths were higher, which is significant for the use of saturated clays as raw materials in ceramic manufacturing. Leaching of Cr from SEP-based material was significantly higher than from KUb-based material probably due to the presence of CaCO3 in the SEP.",
publisher = "Elsevier",
journal = "Applied  Clay Sciences",
title = "Removal of trivalent chromium from aqueous solutions by natural clays: Valorization of saturated adsorbents as raw materials in ceramic manufacturing",
pages = "106747",
volume = "231",
doi = "10.1016/j.clay.2022.106747"
}

Petrović, R., Lazarević, S., Janković-Častvan, I., Matić, T., Milivojević, M., Milošević, D.,& Veljović, Đ.. (2023). Removal of trivalent chromium from aqueous solutions by natural clays: Valorization of saturated adsorbents as raw materials in ceramic manufacturing. in Applied  Clay Sciences
Elsevier., 231, 106747.
https://doi.org/10.1016/j.clay.2022.106747

Petrović R, Lazarević S, Janković-Častvan I, Matić T, Milivojević M, Milošević D, Veljović Đ. Removal of trivalent chromium from aqueous solutions by natural clays: Valorization of saturated adsorbents as raw materials in ceramic manufacturing. in Applied  Clay Sciences. 2023;231:106747.
doi:10.1016/j.clay.2022.106747 .

Petrović, Rada, Lazarević, Slavica, Janković-Častvan, Ivona, Matić, Tamara, Milivojević, Marko, Milošević, Dragana, Veljović, Đorđe, "Removal of trivalent chromium from aqueous solutions by natural clays: Valorization of saturated adsorbents as raw materials in ceramic manufacturing" in Applied  Clay Sciences, 231 (2023):106747,
https://doi.org/10.1016/j.clay.2022.106747 . .

TY  - JOUR
AU  - Janković, Jelena
AU  - Lukić, Jelena
AU  - Kolarski, Dejan
AU  - Veljović, Đorđe
AU  - Radovanović, Željko
AU  - Dimitrijević, Silvana
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6420
AB  - Elemental sulfur (S8) is a corrosive sulfur compound which was found to be extremely reactive to silver, causing intensive silver sulfide (Ag2S) deposition on on-load tap changer (OLTC) contacts in power transformers. A highly selective adsorbent (HSA), called Tesla’Ssorb, for the removal of S8 from mineral insulating oils was prepared from raw material (RM) using the novel procedure. In this study, the adsorption properties of HSA for the removal of S8 from the oil were determined. RM and HSA were characterized using various techniques, such as field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX), and X-ray diffraction (XRD). The performance of HSA was determined by adsorption equilibrium, thermodynamic, and kinetic study through batch experiments, at various temperatures and initial concentrations of S8. The obtained results were analyzed by Langmuir and Freundlich adsorption isotherms and it was found that equilibrium data were fitted better with the Langmuir isotherm model. The maximum adsorption capacity was 4.84 mg of S8/g of HSA at 353 K. Thermodynamic parameters, such as enthalpy (ΔH°), Gibbs free energy (ΔG°), and entropy (ΔS°), were calculated and it was found that the sorption process was spontaneous (ΔG° < 0) and endothermic in nature (ΔH° > 0). It was found that the adsorption of S8 follows pseudo-second-order kinetic model, and the activation energy indicated the activated chemisorption process.
PB  - MDPI
T2  - Materials
T1  - Isotherm, Thermodynamic and Kinetic Studies of Elemental Sulfur Removal from Mineral Insulating Oils Using Highly Selective Adsorbent
IS  - 9
SP  - 3522
VL  - 16
DO  - 10.3390/ma16093522
ER  - 

@article{
author = "Janković, Jelena and Lukić, Jelena and Kolarski, Dejan and Veljović, Đorđe and Radovanović, Željko and Dimitrijević, Silvana",
year = "2023",
abstract = "Elemental sulfur (S8) is a corrosive sulfur compound which was found to be extremely reactive to silver, causing intensive silver sulfide (Ag2S) deposition on on-load tap changer (OLTC) contacts in power transformers. A highly selective adsorbent (HSA), called Tesla’Ssorb, for the removal of S8 from mineral insulating oils was prepared from raw material (RM) using the novel procedure. In this study, the adsorption properties of HSA for the removal of S8 from the oil were determined. RM and HSA were characterized using various techniques, such as field-emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX), and X-ray diffraction (XRD). The performance of HSA was determined by adsorption equilibrium, thermodynamic, and kinetic study through batch experiments, at various temperatures and initial concentrations of S8. The obtained results were analyzed by Langmuir and Freundlich adsorption isotherms and it was found that equilibrium data were fitted better with the Langmuir isotherm model. The maximum adsorption capacity was 4.84 mg of S8/g of HSA at 353 K. Thermodynamic parameters, such as enthalpy (ΔH°), Gibbs free energy (ΔG°), and entropy (ΔS°), were calculated and it was found that the sorption process was spontaneous (ΔG° < 0) and endothermic in nature (ΔH° > 0). It was found that the adsorption of S8 follows pseudo-second-order kinetic model, and the activation energy indicated the activated chemisorption process.",
publisher = "MDPI",
journal = "Materials",
title = "Isotherm, Thermodynamic and Kinetic Studies of Elemental Sulfur Removal from Mineral Insulating Oils Using Highly Selective Adsorbent",
number = "9",
pages = "3522",
volume = "16",
doi = "10.3390/ma16093522"
}

Janković, J., Lukić, J., Kolarski, D., Veljović, Đ., Radovanović, Ž.,& Dimitrijević, S.. (2023). Isotherm, Thermodynamic and Kinetic Studies of Elemental Sulfur Removal from Mineral Insulating Oils Using Highly Selective Adsorbent. in Materials
MDPI., 16(9), 3522.
https://doi.org/10.3390/ma16093522

Janković J, Lukić J, Kolarski D, Veljović Đ, Radovanović Ž, Dimitrijević S. Isotherm, Thermodynamic and Kinetic Studies of Elemental Sulfur Removal from Mineral Insulating Oils Using Highly Selective Adsorbent. in Materials. 2023;16(9):3522.
doi:10.3390/ma16093522 .

Janković, Jelena, Lukić, Jelena, Kolarski, Dejan, Veljović, Đorđe, Radovanović, Željko, Dimitrijević, Silvana, "Isotherm, Thermodynamic and Kinetic Studies of Elemental Sulfur Removal from Mineral Insulating Oils Using Highly Selective Adsorbent" in Materials, 16, no. 9 (2023):3522,
https://doi.org/10.3390/ma16093522 . .

TY  - JOUR
AU  - Ugrinović, Vukašin
AU  - Marković, Maja
AU  - Božić, Bojan
AU  - Panić, Vesna
AU  - Veljović, Đorđe
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6852
AB  - Hydrogels are attractive materials for drug delivery applications due to biocompatible, porous structure with the possibility to load and deliver drugs in a controllable manner. In this paper, poly(methacrylic acid) (PMAA) hydrogels are described, which are synthesized by free-radical polymerization, using poly(ethylene glycol) diacrylate (PEGDA) as a crosslinker. Influence of the PEGDA content on hydrogel properties was investigated and compared to commonly used crosslinker - N,N’-methylenebisacrylamide (MBA). The increasing concentration of crosslinkers led to a higher degree of crosslinking, which was demonstrated by a higher degree of conversion, lower swelling capacity, and improved thermal stability and mechanical properties. Also, the PEGDA-crosslinked hydrogels demonstrated a higher degree of crosslinking than the corresponding MBA-crosslinked hydrogels. Potential application of the synthesized hydrogels for controlled drug delivery was investigated by using two model drugs - oxaprozin and ciprofloxacin. In vitro drug release tests indicated that the interactions between drug, polymer and medium have a key influence on the drug release behavior, rather than the swelling rate. Drug release tests in simulated gastrointestinal conditions indicated that PEGDA-crosslinked PMAA hydrogels are suitable for colon-targeted delivery of oxaprozin.
AB  - Zbog svoje biokompatibilne, visoko-porozne strukture i mogućnosti da nose i kontrolisano
otpuštaju lekove, hidrogelovi su našli široku primenu u biomedicini. U ovom radu,
hidrogelovi na bazi poli(metakrilne kiseline) (PMK), umreženi pomoću poli(etilen-glikol)
diakrilata (PEGDA), sintetisani su metodom toplotno-indukovane slobodno-radikalske
polimerizacije. Ispitan je uticaj sadržaja PEGDA na svojstva hidrogelova i upoređen sa
uticajem najčešće korišćenog umreživača – N,N' – metilenbisakrilamida (MBA). Povećanje
količine oba umreživača dovelo je do većeg stepena umreženja, što je bilo manifestovano
povećanjem stepena konverzije monomera, smanjenjem ravnotežnog stepena bubrenja i
poboljšanim toplotnim i mehaničkim svojstvima. Takođe, hidrogelovi umreženi pomoću
PEGDA pokazali su veći stepen umreženja u odnosu na odgovarajuće hidrogelove umrežene
pomoću MBA. Mogućnost primene dobijenih hidrogelova za kontrolisano otpuštanje lekova,
ispitivano je korišćenjem dva leka – oksaprozina i ciprofloksacina. In vitro testovi
otpuštanja pokazali su da presudan uticaj na kinetiku otpuštanja imaju međusobne interakcije
između leka, hidrogela i medijuma, a ne stepen i brzina bubrenja hidrogela. Prema tome,
otpuštanje ciprofloksacina je bilo intenzivnije u kiseloj sredini, a oksaprozina u baznoj.
Otpuštanje u simuliranim gastrointestinalnim uslovima pokazalo je da su PEGDA-umreženi
hidrogelovi pogodni za kontrolisano otpuštanje oksaprozina u debelo crevo.
PB  - Savez hemijskih inženjera Srbije
T2  - Hemijska industrija
T1  - Poly(methacrylic acid) hydrogels crosslinked by poly(ethylene glycol) diacrylate as pH-responsive systems for drug delivery applications
T1  - Hidrogelovi na bazi poli(metakrilne kiseline) umreženi korišćenjem poli(etilen-glikol) diakrilata, kao pH-osetljivi nosači za kontrolisano otpuštanje lekova
EP  - 249
IS  - 4
SP  - 235
VL  - 77
DO  - 10.2298/HEMIND221228018U
ER  - 

@article{
author = "Ugrinović, Vukašin and Marković, Maja and Božić, Bojan and Panić, Vesna and Veljović, Đorđe",
year = "2023",
abstract = "Hydrogels are attractive materials for drug delivery applications due to biocompatible, porous structure with the possibility to load and deliver drugs in a controllable manner. In this paper, poly(methacrylic acid) (PMAA) hydrogels are described, which are synthesized by free-radical polymerization, using poly(ethylene glycol) diacrylate (PEGDA) as a crosslinker. Influence of the PEGDA content on hydrogel properties was investigated and compared to commonly used crosslinker - N,N’-methylenebisacrylamide (MBA). The increasing concentration of crosslinkers led to a higher degree of crosslinking, which was demonstrated by a higher degree of conversion, lower swelling capacity, and improved thermal stability and mechanical properties. Also, the PEGDA-crosslinked hydrogels demonstrated a higher degree of crosslinking than the corresponding MBA-crosslinked hydrogels. Potential application of the synthesized hydrogels for controlled drug delivery was investigated by using two model drugs - oxaprozin and ciprofloxacin. In vitro drug release tests indicated that the interactions between drug, polymer and medium have a key influence on the drug release behavior, rather than the swelling rate. Drug release tests in simulated gastrointestinal conditions indicated that PEGDA-crosslinked PMAA hydrogels are suitable for colon-targeted delivery of oxaprozin., Zbog svoje biokompatibilne, visoko-porozne strukture i mogućnosti da nose i kontrolisano
otpuštaju lekove, hidrogelovi su našli široku primenu u biomedicini. U ovom radu,
hidrogelovi na bazi poli(metakrilne kiseline) (PMK), umreženi pomoću poli(etilen-glikol)
diakrilata (PEGDA), sintetisani su metodom toplotno-indukovane slobodno-radikalske
polimerizacije. Ispitan je uticaj sadržaja PEGDA na svojstva hidrogelova i upoređen sa
uticajem najčešće korišćenog umreživača – N,N' – metilenbisakrilamida (MBA). Povećanje
količine oba umreživača dovelo je do većeg stepena umreženja, što je bilo manifestovano
povećanjem stepena konverzije monomera, smanjenjem ravnotežnog stepena bubrenja i
poboljšanim toplotnim i mehaničkim svojstvima. Takođe, hidrogelovi umreženi pomoću
PEGDA pokazali su veći stepen umreženja u odnosu na odgovarajuće hidrogelove umrežene
pomoću MBA. Mogućnost primene dobijenih hidrogelova za kontrolisano otpuštanje lekova,
ispitivano je korišćenjem dva leka – oksaprozina i ciprofloksacina. In vitro testovi
otpuštanja pokazali su da presudan uticaj na kinetiku otpuštanja imaju međusobne interakcije
između leka, hidrogela i medijuma, a ne stepen i brzina bubrenja hidrogela. Prema tome,
otpuštanje ciprofloksacina je bilo intenzivnije u kiseloj sredini, a oksaprozina u baznoj.
Otpuštanje u simuliranim gastrointestinalnim uslovima pokazalo je da su PEGDA-umreženi
hidrogelovi pogodni za kontrolisano otpuštanje oksaprozina u debelo crevo.",
publisher = "Savez hemijskih inženjera Srbije",
journal = "Hemijska industrija",
title = "Poly(methacrylic acid) hydrogels crosslinked by poly(ethylene glycol) diacrylate as pH-responsive systems for drug delivery applications, Hidrogelovi na bazi poli(metakrilne kiseline) umreženi korišćenjem poli(etilen-glikol) diakrilata, kao pH-osetljivi nosači za kontrolisano otpuštanje lekova",
pages = "249-235",
number = "4",
volume = "77",
doi = "10.2298/HEMIND221228018U"
}

Ugrinović, V., Marković, M., Božić, B., Panić, V.,& Veljović, Đ.. (2023). Poly(methacrylic acid) hydrogels crosslinked by poly(ethylene glycol) diacrylate as pH-responsive systems for drug delivery applications. in Hemijska industrija
Savez hemijskih inženjera Srbije., 77(4), 235-249.
https://doi.org/10.2298/HEMIND221228018U

Ugrinović V, Marković M, Božić B, Panić V, Veljović Đ. Poly(methacrylic acid) hydrogels crosslinked by poly(ethylene glycol) diacrylate as pH-responsive systems for drug delivery applications. in Hemijska industrija. 2023;77(4):235-249.
doi:10.2298/HEMIND221228018U .

Ugrinović, Vukašin, Marković, Maja, Božić, Bojan, Panić, Vesna, Veljović, Đorđe, "Poly(methacrylic acid) hydrogels crosslinked by poly(ethylene glycol) diacrylate as pH-responsive systems for drug delivery applications" in Hemijska industrija, 77, no. 4 (2023):235-249,
https://doi.org/10.2298/HEMIND221228018U . .

TY  - CONF
AU  - Matić, Tamara
AU  - Ležaja Zebić, Maja
AU  - Miletić, Vesna
AU  - Janaćković, Đorđe
AU  - Veljović, Đorđe
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6685
UR  - https://ecers2023.org/en/program/full-conference-program/34
AB  - The main drawback of resin-based composites (RBCs) widely used in restorative dentistry presents their volumetric shrinkage during the polymerization that can lead to clinical failures of restorations such asmarginal gap formation, bacterial microleakage, fractures, and postoperative sensitivity. To address this problem, sintered hydroxyapatite based dental inserts were introduced in the central part of molar teethrestoration, due to chemical and structural similarities with inorganic part of teeth.
The fabrication of bioceramic dental inserts based on HAP doped with Sr and/or Mg ions presents a way to obtain a dentin substitute that has even greater resemblance to the biological apatite in dentin. However, ion-substitutions arise lattice strain that can have a signifi cant impact on phase composition and properties of apatite materials, especially upon thermal treatment, which could be determining for their further application.
The aims of this study were to comparatively analyze physico-chemical and mechanical properties of the Sr- or Mg-, and Sr+Mg substituted HAP based dental inserts; and evaluate their possible application as dentinsubstitutes. Mono (5 mol. % Sr or Mg ions) and binary- (3 mol.% Sr and 3 mol.% Mg ions) doped HAP nanoparticles were hydrothermally obtained, isostatically pressed into compacts and eventually sintered at 1200°C to obtain dental inserts. The inserts are meant to be adhered to the cavity walls as well as topped with resin composite for sealing and esthetic purposes. Bonding ability of obtained inserts with different commercialrestorative materials, as well as fracture resistance of human molars restored with doped HAP inserts was investigated.
Ion doping was found to infl uence phase compositions of sintered inserts, leading to different mechanical properties and etching behavior of inserts. All inserts showed fracture toughness and bonding ability torestorative materials similar to dentin, while the highest bond strength was obtained for HAP insert doped with 5 mol% Mg (Mg-HAP) bonded to. Fracture resistance of human molars restored with Mg-HAP wasshown to be similar to the fracture resistance of the conventionally restored molars. In conclusion the obtained hydroxyapatite based dental inserts present promising materials for application as dentin substitutes inrestorative dentistry, which have the potential to extend the durability of the restoration.
PB  - European Ceramic Society
C3  - The XVIIIth Conference and Exhibition of the European Ceramic Society (ECerS), Lyon-France, 2-6 July 2023
T1  - Sintered dental inserts based on ion-doped hydroxyapatite as dentin substitutes
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6685
ER  - 

@conference{
author = "Matić, Tamara and Ležaja Zebić, Maja and Miletić, Vesna and Janaćković, Đorđe and Veljović, Đorđe",
year = "2023",
abstract = "The main drawback of resin-based composites (RBCs) widely used in restorative dentistry presents their volumetric shrinkage during the polymerization that can lead to clinical failures of restorations such asmarginal gap formation, bacterial microleakage, fractures, and postoperative sensitivity. To address this problem, sintered hydroxyapatite based dental inserts were introduced in the central part of molar teethrestoration, due to chemical and structural similarities with inorganic part of teeth.
The fabrication of bioceramic dental inserts based on HAP doped with Sr and/or Mg ions presents a way to obtain a dentin substitute that has even greater resemblance to the biological apatite in dentin. However, ion-substitutions arise lattice strain that can have a signifi cant impact on phase composition and properties of apatite materials, especially upon thermal treatment, which could be determining for their further application.
The aims of this study were to comparatively analyze physico-chemical and mechanical properties of the Sr- or Mg-, and Sr+Mg substituted HAP based dental inserts; and evaluate their possible application as dentinsubstitutes. Mono (5 mol. % Sr or Mg ions) and binary- (3 mol.% Sr and 3 mol.% Mg ions) doped HAP nanoparticles were hydrothermally obtained, isostatically pressed into compacts and eventually sintered at 1200°C to obtain dental inserts. The inserts are meant to be adhered to the cavity walls as well as topped with resin composite for sealing and esthetic purposes. Bonding ability of obtained inserts with different commercialrestorative materials, as well as fracture resistance of human molars restored with doped HAP inserts was investigated.
Ion doping was found to infl uence phase compositions of sintered inserts, leading to different mechanical properties and etching behavior of inserts. All inserts showed fracture toughness and bonding ability torestorative materials similar to dentin, while the highest bond strength was obtained for HAP insert doped with 5 mol% Mg (Mg-HAP) bonded to. Fracture resistance of human molars restored with Mg-HAP wasshown to be similar to the fracture resistance of the conventionally restored molars. In conclusion the obtained hydroxyapatite based dental inserts present promising materials for application as dentin substitutes inrestorative dentistry, which have the potential to extend the durability of the restoration.",
publisher = "European Ceramic Society",
journal = "The XVIIIth Conference and Exhibition of the European Ceramic Society (ECerS), Lyon-France, 2-6 July 2023",
title = "Sintered dental inserts based on ion-doped hydroxyapatite as dentin substitutes",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6685"
}

Matić, T., Ležaja Zebić, M., Miletić, V., Janaćković, Đ.,& Veljović, Đ.. (2023). Sintered dental inserts based on ion-doped hydroxyapatite as dentin substitutes. in The XVIIIth Conference and Exhibition of the European Ceramic Society (ECerS), Lyon-France, 2-6 July 2023
European Ceramic Society..
https://hdl.handle.net/21.15107/rcub_technorep_6685

Matić T, Ležaja Zebić M, Miletić V, Janaćković Đ, Veljović Đ. Sintered dental inserts based on ion-doped hydroxyapatite as dentin substitutes. in The XVIIIth Conference and Exhibition of the European Ceramic Society (ECerS), Lyon-France, 2-6 July 2023. 2023;.
https://hdl.handle.net/21.15107/rcub_technorep_6685 .

Matić, Tamara, Ležaja Zebić, Maja, Miletić, Vesna, Janaćković, Đorđe, Veljović, Đorđe, "Sintered dental inserts based on ion-doped hydroxyapatite as dentin substitutes" in The XVIIIth Conference and Exhibition of the European Ceramic Society (ECerS), Lyon-France, 2-6 July 2023 (2023),
https://hdl.handle.net/21.15107/rcub_technorep_6685 .

TY  - CONF
AU  - Mihajlović, Dragana
AU  - Rakin, Marko
AU  - Veljović, Đorđe
AU  - Međo, Bojan
AU  - Đokić, Veljko
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/7011
AB  - The coarse-grained (CG) and ultrafine-grained (UFG) Ti-13Nb-13Zr alloy (TNZ) were used as tested materials in this
study. UFG alloy was obtained using a high-pressure torsion process (HPT) at room temperature, with 5 rotations, and
with 4.1 GPa pressure. After that, the surface was modified using electrochemical anodization in the 1M H3PO4 + NaF
electrolyte, for 60 and 90 minutes.
Scanning electron microscopy (SEM) was used to characterize the morphology of the modified surface after
electrochemical anodization. In order to determine whether the electrochemical anodization leads to obtaining the
surface modulus of elasticity values close to the values characteristic of the human bones, a nanoindentation test was
done. The nanoindentation test was performed on the device called nanoindenter G200, Agilent Technologies, where
a diamond tip of the Berkovich type shaped as a three-sided pyramid was used as an indenter. Control of
the nanoindentation test was done by nanoindentation depth, where for non-anodized materials a depth of 2000 nm was
used, while for anodized materials a minimum value of 10% of the thickness of the formed nanostructured oxide layer
was used. Biocompatibility of the tested titanium alloy was estimated by the tetrazolium salt colorimetric test
(MTT test) using mouse fibroblasts (L-929) and human lung fibroblasts (MRC-5). The cell adhesion on the alloy
surface was analyzed using SEM.
Electrochemical anodization has led to the formation of the nanostructured oxide layer on the titanium alloy surface.
The obtained results show the existence of the influence of anodizing time on the nanostructured oxide layer
morphology. Characterization of the titanium alloy surface using nanoindentation showed a decrease in the values
of modulus of elasticity for an alloy with a nanostructured oxide layer, which is close to the values of bone tissue in
the human body. The results of the MTT test showed that the titanium alloys before and after electrochemical
anodization were not cytotoxic. After electrochemical anodization, a uniform nanostructured surface, with nanotubes,
was formed which led to better cell viability and adhesion of L-929 and MRC-5 cells in contact with the test alloys than
of cells in contact with the control material.
PB  - Belgrade : Association of Metallurgical Engineers of Serbia (AMES)
C3  - Book of Abstracts / 5th Metallurgical & Materials Engineering Congress of SouthEast Europe MME SEE Congress 2023, Trebinje, Bosnia and Herzegovina 7-10th June 2023
T1  - Advancement of biocompatibility and mechanical surface characteristics of the Ti-13Nb-13Zr alloy using electrochemical anodization
SP  - 56
UR  - https://hdl.handle.net/21.15107/rcub_technorep_7011
ER  - 

@conference{
author = "Mihajlović, Dragana and Rakin, Marko and Veljović, Đorđe and Međo, Bojan and Đokić, Veljko",
year = "2023",
abstract = "The coarse-grained (CG) and ultrafine-grained (UFG) Ti-13Nb-13Zr alloy (TNZ) were used as tested materials in this
study. UFG alloy was obtained using a high-pressure torsion process (HPT) at room temperature, with 5 rotations, and
with 4.1 GPa pressure. After that, the surface was modified using electrochemical anodization in the 1M H3PO4 + NaF
electrolyte, for 60 and 90 minutes.
Scanning electron microscopy (SEM) was used to characterize the morphology of the modified surface after
electrochemical anodization. In order to determine whether the electrochemical anodization leads to obtaining the
surface modulus of elasticity values close to the values characteristic of the human bones, a nanoindentation test was
done. The nanoindentation test was performed on the device called nanoindenter G200, Agilent Technologies, where
a diamond tip of the Berkovich type shaped as a three-sided pyramid was used as an indenter. Control of
the nanoindentation test was done by nanoindentation depth, where for non-anodized materials a depth of 2000 nm was
used, while for anodized materials a minimum value of 10% of the thickness of the formed nanostructured oxide layer
was used. Biocompatibility of the tested titanium alloy was estimated by the tetrazolium salt colorimetric test
(MTT test) using mouse fibroblasts (L-929) and human lung fibroblasts (MRC-5). The cell adhesion on the alloy
surface was analyzed using SEM.
Electrochemical anodization has led to the formation of the nanostructured oxide layer on the titanium alloy surface.
The obtained results show the existence of the influence of anodizing time on the nanostructured oxide layer
morphology. Characterization of the titanium alloy surface using nanoindentation showed a decrease in the values
of modulus of elasticity for an alloy with a nanostructured oxide layer, which is close to the values of bone tissue in
the human body. The results of the MTT test showed that the titanium alloys before and after electrochemical
anodization were not cytotoxic. After electrochemical anodization, a uniform nanostructured surface, with nanotubes,
was formed which led to better cell viability and adhesion of L-929 and MRC-5 cells in contact with the test alloys than
of cells in contact with the control material.",
publisher = "Belgrade : Association of Metallurgical Engineers of Serbia (AMES)",
journal = "Book of Abstracts / 5th Metallurgical & Materials Engineering Congress of SouthEast Europe MME SEE Congress 2023, Trebinje, Bosnia and Herzegovina 7-10th June 2023",
title = "Advancement of biocompatibility and mechanical surface characteristics of the Ti-13Nb-13Zr alloy using electrochemical anodization",
pages = "56",
url = "https://hdl.handle.net/21.15107/rcub_technorep_7011"
}

Mihajlović, D., Rakin, M., Veljović, Đ., Međo, B.,& Đokić, V.. (2023). Advancement of biocompatibility and mechanical surface characteristics of the Ti-13Nb-13Zr alloy using electrochemical anodization. in Book of Abstracts / 5th Metallurgical & Materials Engineering Congress of SouthEast Europe MME SEE Congress 2023, Trebinje, Bosnia and Herzegovina 7-10th June 2023
Belgrade : Association of Metallurgical Engineers of Serbia (AMES)., 56.
https://hdl.handle.net/21.15107/rcub_technorep_7011

Mihajlović D, Rakin M, Veljović Đ, Međo B, Đokić V. Advancement of biocompatibility and mechanical surface characteristics of the Ti-13Nb-13Zr alloy using electrochemical anodization. in Book of Abstracts / 5th Metallurgical & Materials Engineering Congress of SouthEast Europe MME SEE Congress 2023, Trebinje, Bosnia and Herzegovina 7-10th June 2023. 2023;:56.
https://hdl.handle.net/21.15107/rcub_technorep_7011 .

Mihajlović, Dragana, Rakin, Marko, Veljović, Đorđe, Međo, Bojan, Đokić, Veljko, "Advancement of biocompatibility and mechanical surface characteristics of the Ti-13Nb-13Zr alloy using electrochemical anodization" in Book of Abstracts / 5th Metallurgical & Materials Engineering Congress of SouthEast Europe MME SEE Congress 2023, Trebinje, Bosnia and Herzegovina 7-10th June 2023 (2023):56,
https://hdl.handle.net/21.15107/rcub_technorep_7011 .

TY  - CONF
AU  - Zvicer, Jovana
AU  - Stojkovska, Jasmina
AU  - Milošević, Mia
AU  - Veljović, Đorđe
AU  - Obradović, Bojana
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6956
AB  - Development of novel biomaterials for use in biomedical applications requires careful assessment due to the intended interactions with cells and tissues. Understanding biocompatibility, non-toxicity, and capability of promoting desired biological responses requires thorough characterization of biomaterial, including its chemical composition, surface properties, mechanical strength, degradation rate, etc. Traditional in vitro methods for evaluating biomaterials in cell monolayers are convenient but limited by the lack of specific biophysical signals found in vivo, which can lead to unreliable results. This in vitro-in vivo gap can result in the unnecessary sacrifice of a large number of animals for testing purposes. Therefore, there is a need for alternative approaches that beter mimic the in vivo environment and accurately predict the behavior of the biomaterial after implantation. Biomimetic bioreactors are primarily developed for tissue engineering to provide the key biochemical (e.g., nutrients, gases, growth factors) and biophysical signals (e.g., shear stress, hydrostatic pressure, mechanical strains) found in vivo and thus could be indispensable tools in physiologically relevant biomaterial assessment. Our group introduced the application of two biomimetic bioreactors for the physiologically relevant characterization of two types of composite biomaterials aimed for bone and osteochondral tissue engineering. In specific, macroporous composite scaffolds were produced using two natural polymers (gellan gum and alginate) as matrices imitating organic phase of bone tissue with incorporated particulate bioactive glass (BAG) and β-tricalcium phosphate (β-TCP) as hydroxyapatite (HAp) precursors. In addition, in osteochondral scaffolds, gellan gum hydrogel served as a cartilaginous layer on top of the porous composite base. Integrity and mechanical properties of all prepared scaffolds were monitored for 14 days under physiological levels of mechanical compression (up to 10% strain, compression rate 337.5 µm s-1) in a bioreactor with dynamic compression and medium perfusion. Bioactivity and HAp formation within the scaffolds were investigated in a perfusion bioreactor under the flow of simulated body fluid for up to 28 days. The scaffolds were assessed by SEM, EDS, and XRD analyses indicating a significant increase in HAp formation under bioreactor conditions as compared to static controls in all investigated samples. Moreover, the formed HAp crystals were more uniformly distributed throughout the scaffolds showing a more cauliflower-like morphology and thus, indicating potentials for bone/osteochondral tissue engineering applications. The obtained results confirm the high influence of experimental conditions on the outcomes of biomaterial characterization and importance of closely mimicking physiological conditions, thus puting forward biomimetic bioreactors as a means in this direction.
PB  - Davos : AO Research Institute
C3  - ARI Abstracts Periodical
T1  - BIOMIMETIC BIOREACTORS AS A TOOL FOR MORE RELEVANT BIOMATERIAL ASSESSMENT
IS  - Collection 3
SP  - 313
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6956
ER  - 

@conference{
author = "Zvicer, Jovana and Stojkovska, Jasmina and Milošević, Mia and Veljović, Đorđe and Obradović, Bojana",
year = "2023",
abstract = "Development of novel biomaterials for use in biomedical applications requires careful assessment due to the intended interactions with cells and tissues. Understanding biocompatibility, non-toxicity, and capability of promoting desired biological responses requires thorough characterization of biomaterial, including its chemical composition, surface properties, mechanical strength, degradation rate, etc. Traditional in vitro methods for evaluating biomaterials in cell monolayers are convenient but limited by the lack of specific biophysical signals found in vivo, which can lead to unreliable results. This in vitro-in vivo gap can result in the unnecessary sacrifice of a large number of animals for testing purposes. Therefore, there is a need for alternative approaches that beter mimic the in vivo environment and accurately predict the behavior of the biomaterial after implantation. Biomimetic bioreactors are primarily developed for tissue engineering to provide the key biochemical (e.g., nutrients, gases, growth factors) and biophysical signals (e.g., shear stress, hydrostatic pressure, mechanical strains) found in vivo and thus could be indispensable tools in physiologically relevant biomaterial assessment. Our group introduced the application of two biomimetic bioreactors for the physiologically relevant characterization of two types of composite biomaterials aimed for bone and osteochondral tissue engineering. In specific, macroporous composite scaffolds were produced using two natural polymers (gellan gum and alginate) as matrices imitating organic phase of bone tissue with incorporated particulate bioactive glass (BAG) and β-tricalcium phosphate (β-TCP) as hydroxyapatite (HAp) precursors. In addition, in osteochondral scaffolds, gellan gum hydrogel served as a cartilaginous layer on top of the porous composite base. Integrity and mechanical properties of all prepared scaffolds were monitored for 14 days under physiological levels of mechanical compression (up to 10% strain, compression rate 337.5 µm s-1) in a bioreactor with dynamic compression and medium perfusion. Bioactivity and HAp formation within the scaffolds were investigated in a perfusion bioreactor under the flow of simulated body fluid for up to 28 days. The scaffolds were assessed by SEM, EDS, and XRD analyses indicating a significant increase in HAp formation under bioreactor conditions as compared to static controls in all investigated samples. Moreover, the formed HAp crystals were more uniformly distributed throughout the scaffolds showing a more cauliflower-like morphology and thus, indicating potentials for bone/osteochondral tissue engineering applications. The obtained results confirm the high influence of experimental conditions on the outcomes of biomaterial characterization and importance of closely mimicking physiological conditions, thus puting forward biomimetic bioreactors as a means in this direction.",
publisher = "Davos : AO Research Institute",
journal = "ARI Abstracts Periodical",
title = "BIOMIMETIC BIOREACTORS AS A TOOL FOR MORE RELEVANT BIOMATERIAL ASSESSMENT",
number = "Collection 3",
pages = "313",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6956"
}

Zvicer, J., Stojkovska, J., Milošević, M., Veljović, Đ.,& Obradović, B.. (2023). BIOMIMETIC BIOREACTORS AS A TOOL FOR MORE RELEVANT BIOMATERIAL ASSESSMENT. in ARI Abstracts Periodical
Davos : AO Research Institute.(Collection 3), 313.
https://hdl.handle.net/21.15107/rcub_technorep_6956

Zvicer J, Stojkovska J, Milošević M, Veljović Đ, Obradović B. BIOMIMETIC BIOREACTORS AS A TOOL FOR MORE RELEVANT BIOMATERIAL ASSESSMENT. in ARI Abstracts Periodical. 2023;(Collection 3):313.
https://hdl.handle.net/21.15107/rcub_technorep_6956 .

Zvicer, Jovana, Stojkovska, Jasmina, Milošević, Mia, Veljović, Đorđe, Obradović, Bojana, "BIOMIMETIC BIOREACTORS AS A TOOL FOR MORE RELEVANT BIOMATERIAL ASSESSMENT" in ARI Abstracts Periodical, no. Collection 3 (2023):313,
https://hdl.handle.net/21.15107/rcub_technorep_6956 .

TY  - CONF
AU  - Zvicer, Jovana
AU  - Stojkovska, Jasmina
AU  - Veljović, Đorđe
AU  - Milošević, Mia
AU  - Obradović, Bojana
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6957
AB  - Comprehensive preclinical studies are essential for the development of novel biomaterials that can be used in biomedical applications. However, traditional methods used for the evaluation of biomaterials have certain limitations. In vitro testing in cell monolayers is fast and easily accessible, but the 2D environment can affect cell metabolism and morphology, leading to unreliable results. On the other hand, in vivo animal studies are complex, time-consuming, expensive, and raise ethical concerns. Biomimetic bioreactors, primarily developed for tissue engineering to provide a physiologically relevant, strictly controlled environment that mimics the conditions in specific tissues or organs, could be indispensable tools in physiologically relevant biomaterial characterization and step between in vitro and in vivo studies. They offer the majority or all the necessary biochemical (e.g. pH, nutrients, gases, growth factors) and biophysical signals (e.g., shear stress, hydrostatic pressure, mechanical strains) highly relevant for biomaterial assessment and prediction of material behavior after implantation. Our group has developed two types of potential biomaterials aimed for bone and osteochondral tissue engineering based on bioactive glass (BAG), β-tricalcium phosphate (β-TCP), and different natural polymers (gellan gum and alginate). Scaffolds' integrity and mechanical properties were monitored continuously under the physiological level of mechanical compression using a dynamic compression bioreactor coupled with medium perfusion during 14 days. Formation of hydroxyapatite (HAp) within the scaffolds was investigated in a perfusion bioreactor, in the presence of simulated body fluid (SBF) during 14 and 28 days for scaffolds based on BAG and β-TCP, respectively. SEM, EDS, and XRD results have shown a significant increase in the formation of HAp under bioreactor conditions compared to static control conditions. Beyond that, formed HAp crystals were more uniformly distributed throughout scaffolds and presented more cauliflower-like morphology. The obtained results demonstrated the utilization potential of biomimetic bioreactors in physiologically relevant biomaterial characterization.
C3  - Book of Abstract / 3rd YCN Workshop, 19th to 21st April 2023, Aveiro, Portugal
T1  - HOW NOVEL BIOMATERIALS BASED ON BIOACTIVE GLASS AND β-TRICALCIUM PHOSPHATE CAN BE EVALUATED UNDER PHYSIOLOGICALLY RELEVANT CONDITIONS?
SP  - 23
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6957
ER  - 

@conference{
author = "Zvicer, Jovana and Stojkovska, Jasmina and Veljović, Đorđe and Milošević, Mia and Obradović, Bojana",
year = "2023",
abstract = "Comprehensive preclinical studies are essential for the development of novel biomaterials that can be used in biomedical applications. However, traditional methods used for the evaluation of biomaterials have certain limitations. In vitro testing in cell monolayers is fast and easily accessible, but the 2D environment can affect cell metabolism and morphology, leading to unreliable results. On the other hand, in vivo animal studies are complex, time-consuming, expensive, and raise ethical concerns. Biomimetic bioreactors, primarily developed for tissue engineering to provide a physiologically relevant, strictly controlled environment that mimics the conditions in specific tissues or organs, could be indispensable tools in physiologically relevant biomaterial characterization and step between in vitro and in vivo studies. They offer the majority or all the necessary biochemical (e.g. pH, nutrients, gases, growth factors) and biophysical signals (e.g., shear stress, hydrostatic pressure, mechanical strains) highly relevant for biomaterial assessment and prediction of material behavior after implantation. Our group has developed two types of potential biomaterials aimed for bone and osteochondral tissue engineering based on bioactive glass (BAG), β-tricalcium phosphate (β-TCP), and different natural polymers (gellan gum and alginate). Scaffolds' integrity and mechanical properties were monitored continuously under the physiological level of mechanical compression using a dynamic compression bioreactor coupled with medium perfusion during 14 days. Formation of hydroxyapatite (HAp) within the scaffolds was investigated in a perfusion bioreactor, in the presence of simulated body fluid (SBF) during 14 and 28 days for scaffolds based on BAG and β-TCP, respectively. SEM, EDS, and XRD results have shown a significant increase in the formation of HAp under bioreactor conditions compared to static control conditions. Beyond that, formed HAp crystals were more uniformly distributed throughout scaffolds and presented more cauliflower-like morphology. The obtained results demonstrated the utilization potential of biomimetic bioreactors in physiologically relevant biomaterial characterization.",
journal = "Book of Abstract / 3rd YCN Workshop, 19th to 21st April 2023, Aveiro, Portugal",
title = "HOW NOVEL BIOMATERIALS BASED ON BIOACTIVE GLASS AND β-TRICALCIUM PHOSPHATE CAN BE EVALUATED UNDER PHYSIOLOGICALLY RELEVANT CONDITIONS?",
pages = "23",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6957"
}

Zvicer, J., Stojkovska, J., Veljović, Đ., Milošević, M.,& Obradović, B.. (2023). HOW NOVEL BIOMATERIALS BASED ON BIOACTIVE GLASS AND β-TRICALCIUM PHOSPHATE CAN BE EVALUATED UNDER PHYSIOLOGICALLY RELEVANT CONDITIONS?. in Book of Abstract / 3rd YCN Workshop, 19th to 21st April 2023, Aveiro, Portugal, 23.
https://hdl.handle.net/21.15107/rcub_technorep_6957

Zvicer J, Stojkovska J, Veljović Đ, Milošević M, Obradović B. HOW NOVEL BIOMATERIALS BASED ON BIOACTIVE GLASS AND β-TRICALCIUM PHOSPHATE CAN BE EVALUATED UNDER PHYSIOLOGICALLY RELEVANT CONDITIONS?. in Book of Abstract / 3rd YCN Workshop, 19th to 21st April 2023, Aveiro, Portugal. 2023;:23.
https://hdl.handle.net/21.15107/rcub_technorep_6957 .

Zvicer, Jovana, Stojkovska, Jasmina, Veljović, Đorđe, Milošević, Mia, Obradović, Bojana, "HOW NOVEL BIOMATERIALS BASED ON BIOACTIVE GLASS AND β-TRICALCIUM PHOSPHATE CAN BE EVALUATED UNDER PHYSIOLOGICALLY RELEVANT CONDITIONS?" in Book of Abstract / 3rd YCN Workshop, 19th to 21st April 2023, Aveiro, Portugal (2023):23,
https://hdl.handle.net/21.15107/rcub_technorep_6957 .

TY  - JOUR
AU  - Galić, Aleksa
AU  - Matić, Tamara
AU  - Obradović, Nataša
AU  - Baščarević, Zvezdana
AU  - Veljović, Đorđe
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/7282
AB  - Limited bone bank capacity and risk of infection are some of the main drawbacks of autologous and allogenic grafts, giving rise to synthetic materials for bone tissue implants. The aim of this study was to process and evaluate the mechanical properties and bioactivity of magnesium and strontium doped hydroxyapatite (HAp) scaffolds and investigate the effect of adding zirconium oxide and gelatine coating the scaffolds. Doped nanosized hydroxyapatite powder was synthesized by the hydrothermal method and the scaffolds were made by the foam replica technique and sintered at different temperatures. Yttria-stabilized zirconium oxide (YSZ), synthesized by plasma technology, was used as reinforcement of calcium phosphate scaffolds. Element analysis, phase composition, morphology of the powders and microstructure of the scaffolds were investigated, as well as the compressive strength of the coated and uncoated scaffolds and bioactivity in simulated body fluid (SBF). A microporous structure was achieved with interconnected pores and bioactivity in SBF was confirmed in all cases. The best mechanical properties were given by the coated composite HAp/YSZ scaffolds, withstanding average stresses of over 1019 kPa. These results encourage the idea of use of these scaffolds in bone regenerative therapy and bone tissue engineering.
PB  - International Institute for the Science of Sintering
T2  - Science of Sintering
T1  - Processing of gelatine coated composite scaffolds based on magnesium and strontium doped hydroxyapatite and yttria-stabilized zirconium oxide
EP  - 479
IS  - 4
SP  - 469
VL  - 55
DO  - 10.2298/SOS220723019G
ER  - 

@article{
author = "Galić, Aleksa and Matić, Tamara and Obradović, Nataša and Baščarević, Zvezdana and Veljović, Đorđe",
year = "2023",
abstract = "Limited bone bank capacity and risk of infection are some of the main drawbacks of autologous and allogenic grafts, giving rise to synthetic materials for bone tissue implants. The aim of this study was to process and evaluate the mechanical properties and bioactivity of magnesium and strontium doped hydroxyapatite (HAp) scaffolds and investigate the effect of adding zirconium oxide and gelatine coating the scaffolds. Doped nanosized hydroxyapatite powder was synthesized by the hydrothermal method and the scaffolds were made by the foam replica technique and sintered at different temperatures. Yttria-stabilized zirconium oxide (YSZ), synthesized by plasma technology, was used as reinforcement of calcium phosphate scaffolds. Element analysis, phase composition, morphology of the powders and microstructure of the scaffolds were investigated, as well as the compressive strength of the coated and uncoated scaffolds and bioactivity in simulated body fluid (SBF). A microporous structure was achieved with interconnected pores and bioactivity in SBF was confirmed in all cases. The best mechanical properties were given by the coated composite HAp/YSZ scaffolds, withstanding average stresses of over 1019 kPa. These results encourage the idea of use of these scaffolds in bone regenerative therapy and bone tissue engineering.",
publisher = "International Institute for the Science of Sintering",
journal = "Science of Sintering",
title = "Processing of gelatine coated composite scaffolds based on magnesium and strontium doped hydroxyapatite and yttria-stabilized zirconium oxide",
pages = "479-469",
number = "4",
volume = "55",
doi = "10.2298/SOS220723019G"
}

Galić, A., Matić, T., Obradović, N., Baščarević, Z.,& Veljović, Đ.. (2023). Processing of gelatine coated composite scaffolds based on magnesium and strontium doped hydroxyapatite and yttria-stabilized zirconium oxide. in Science of Sintering
International Institute for the Science of Sintering., 55(4), 469-479.
https://doi.org/10.2298/SOS220723019G

Galić A, Matić T, Obradović N, Baščarević Z, Veljović Đ. Processing of gelatine coated composite scaffolds based on magnesium and strontium doped hydroxyapatite and yttria-stabilized zirconium oxide. in Science of Sintering. 2023;55(4):469-479.
doi:10.2298/SOS220723019G .

Galić, Aleksa, Matić, Tamara, Obradović, Nataša, Baščarević, Zvezdana, Veljović, Đorđe, "Processing of gelatine coated composite scaffolds based on magnesium and strontium doped hydroxyapatite and yttria-stabilized zirconium oxide" in Science of Sintering, 55, no. 4 (2023):469-479,
https://doi.org/10.2298/SOS220723019G . .

TY  - JOUR
AU  - Laban, Bojana B.
AU  - Lazarević-Pašti, Tamara
AU  - Veljović, Đorđe
AU  - Marković, Mirjana
AU  - Klekotka, Urszula
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6222
AB  - The silver and gold L-methionine capped nanoparticles (Ag and Au @LM NPs) were analyzed as prospective acetylcholinesterase (AChE) inhibitors to test their potential in the treatment of cognitive impairment in depression and Alzheimer's disease. The stability of NPs, and their ability to inhibit AChE were studied by UV-Vis and FTIR spectrophotometry. At the same time, TEM and SEM measurements, DLS, and zeta potential measurements were employed in the structural characterization of NPs. Nearly spherical, negatively charged Ag and Au @LM NPs, with 17 nm and 31 nm in diameter, respectively, showed moderate inhibitory potential toward AChE in the given frame of investigated concentrations. For both NPs IC50 is not reached. Furthermore, the adsorption of enzyme molecules on the surface of Ag and Au @LM NPs was demonstrated. Hence, our assumption is that inhibition of AChE is caused by blockage of the enzyme‘s active site due to the steric hindrance of NPs.
PB  - John Wiley and Sons Inc.
T2  - European Journal of Inorganic Chemistry
T1  - Methionine Capped Nanoparticles as Acetylcholinesterase Inhibitors
SP  - e202200754
DO  - 10.1002/ejic.202200754
ER  - 

@article{
author = "Laban, Bojana B. and Lazarević-Pašti, Tamara and Veljović, Đorđe and Marković, Mirjana and Klekotka, Urszula",
year = "2023",
abstract = "The silver and gold L-methionine capped nanoparticles (Ag and Au @LM NPs) were analyzed as prospective acetylcholinesterase (AChE) inhibitors to test their potential in the treatment of cognitive impairment in depression and Alzheimer's disease. The stability of NPs, and their ability to inhibit AChE were studied by UV-Vis and FTIR spectrophotometry. At the same time, TEM and SEM measurements, DLS, and zeta potential measurements were employed in the structural characterization of NPs. Nearly spherical, negatively charged Ag and Au @LM NPs, with 17 nm and 31 nm in diameter, respectively, showed moderate inhibitory potential toward AChE in the given frame of investigated concentrations. For both NPs IC50 is not reached. Furthermore, the adsorption of enzyme molecules on the surface of Ag and Au @LM NPs was demonstrated. Hence, our assumption is that inhibition of AChE is caused by blockage of the enzyme‘s active site due to the steric hindrance of NPs.",
publisher = "John Wiley and Sons Inc.",
journal = "European Journal of Inorganic Chemistry",
title = "Methionine Capped Nanoparticles as Acetylcholinesterase Inhibitors",
pages = "e202200754",
doi = "10.1002/ejic.202200754"
}

Laban, B. B., Lazarević-Pašti, T., Veljović, Đ., Marković, M.,& Klekotka, U.. (2023). Methionine Capped Nanoparticles as Acetylcholinesterase Inhibitors. in European Journal of Inorganic Chemistry
John Wiley and Sons Inc.., e202200754.
https://doi.org/10.1002/ejic.202200754

Laban BB, Lazarević-Pašti T, Veljović Đ, Marković M, Klekotka U. Methionine Capped Nanoparticles as Acetylcholinesterase Inhibitors. in European Journal of Inorganic Chemistry. 2023;:e202200754.
doi:10.1002/ejic.202200754 .

Laban, Bojana B., Lazarević-Pašti, Tamara, Veljović, Đorđe, Marković, Mirjana, Klekotka, Urszula, "Methionine Capped Nanoparticles as Acetylcholinesterase Inhibitors" in European Journal of Inorganic Chemistry (2023):e202200754,
https://doi.org/10.1002/ejic.202200754 . .

TY  - CONF
AU  - Grbić, Jovana
AU  - Mladenović, Dragana
AU  - Pavlović, Stefan
AU  - Veljović, Đorđe
AU  - Lazović, Saša
AU  - Đukić-Vuković, Aleksandra
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6344
AB  - Corn is one of the world´s most commonly cultivated crops.A major part of the plant remaining after harvesting is the corn stalk.This corn residueis rich in carbohydrates and could be suitable for the fermentative production of numerous value-added products. The corn stalk’s complex structure, recalcitrance deriving from lignin, and high crystallinity and polymerization degree of cellulose prevent conventional pretreatment techniques to separate it efficiently into elementary fractions. Therefore, it is usually processed by burning directly on the ground or landfilling.It seldom can be used for composting or combusted for heat generation. In this study, different advanced oxidation processes were used for the treatment of corn stalks to enable more sustainable valorization of biomass by enzymatic hydrolysis. The effects of non-thermal plasma treatment, treatment with Fenton reagent, and combined non-thermal plasma/Fenton treatment on lignocellulose degradation and biomass digestibility were monitored. Treatment efficacy in terms of degradation was assessed by determininglignincontent. Structural and textural properties of treated biomass were analyzed using FTIR analysis and mercury intrusion porosimetry (MIP).The carbohydrate digestibility estimation was based on hexose and pentose content in hydrolyzed samples. Applied treatments showed success in breaking complex lignocellulose structures. The delignification rates for the non-thermal plasma treated sample, thesample treated only with the Fenton reagent, and the combined non-thermal plasma/Fenton treated sample were 19%, 28.7%, and 53%, respectively. Selectivity towards lignin increased with prolonging the non-thermal plasma treatmentorthe addition of the Fenton reagent.To achieve a delignification rateof 53% by using only non-thermal plasma, treatment should last at least 60 minutes. When the Fenton reagent is added, the same result is obtained with a halved duration of the plasma treatment. Under these conditions, pore size diameter in treated biomass increased, resulting in enhanced biomass digestibility with 2.25 times higher hexose yield compared to the untreated sample. This is a significant step forward in developing sustainable treatments for lignocellulosic biomass, which is especially important in biorefinery processes.
PB  - University of East Sarajevo Faculty of Technology
C3  - Book of abstracts VIII International congress Engineering, environment and materials in process industry
T1  - Effect of combined non-thermal plasma/Fenton treatment on lignocellulose degradation in corn stalks
SP  - 154
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6344
ER  - 

@conference{
author = "Grbić, Jovana and Mladenović, Dragana and Pavlović, Stefan and Veljović, Đorđe and Lazović, Saša and Đukić-Vuković, Aleksandra",
year = "2023",
abstract = "Corn is one of the world´s most commonly cultivated crops.A major part of the plant remaining after harvesting is the corn stalk.This corn residueis rich in carbohydrates and could be suitable for the fermentative production of numerous value-added products. The corn stalk’s complex structure, recalcitrance deriving from lignin, and high crystallinity and polymerization degree of cellulose prevent conventional pretreatment techniques to separate it efficiently into elementary fractions. Therefore, it is usually processed by burning directly on the ground or landfilling.It seldom can be used for composting or combusted for heat generation. In this study, different advanced oxidation processes were used for the treatment of corn stalks to enable more sustainable valorization of biomass by enzymatic hydrolysis. The effects of non-thermal plasma treatment, treatment with Fenton reagent, and combined non-thermal plasma/Fenton treatment on lignocellulose degradation and biomass digestibility were monitored. Treatment efficacy in terms of degradation was assessed by determininglignincontent. Structural and textural properties of treated biomass were analyzed using FTIR analysis and mercury intrusion porosimetry (MIP).The carbohydrate digestibility estimation was based on hexose and pentose content in hydrolyzed samples. Applied treatments showed success in breaking complex lignocellulose structures. The delignification rates for the non-thermal plasma treated sample, thesample treated only with the Fenton reagent, and the combined non-thermal plasma/Fenton treated sample were 19%, 28.7%, and 53%, respectively. Selectivity towards lignin increased with prolonging the non-thermal plasma treatmentorthe addition of the Fenton reagent.To achieve a delignification rateof 53% by using only non-thermal plasma, treatment should last at least 60 minutes. When the Fenton reagent is added, the same result is obtained with a halved duration of the plasma treatment. Under these conditions, pore size diameter in treated biomass increased, resulting in enhanced biomass digestibility with 2.25 times higher hexose yield compared to the untreated sample. This is a significant step forward in developing sustainable treatments for lignocellulosic biomass, which is especially important in biorefinery processes.",
publisher = "University of East Sarajevo Faculty of Technology",
journal = "Book of abstracts VIII International congress Engineering, environment and materials in process industry",
title = "Effect of combined non-thermal plasma/Fenton treatment on lignocellulose degradation in corn stalks",
pages = "154",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6344"
}

Grbić, J., Mladenović, D., Pavlović, S., Veljović, Đ., Lazović, S.,& Đukić-Vuković, A.. (2023). Effect of combined non-thermal plasma/Fenton treatment on lignocellulose degradation in corn stalks. in Book of abstracts VIII International congress Engineering, environment and materials in process industry
University of East Sarajevo Faculty of Technology., 154.
https://hdl.handle.net/21.15107/rcub_technorep_6344

Grbić J, Mladenović D, Pavlović S, Veljović Đ, Lazović S, Đukić-Vuković A. Effect of combined non-thermal plasma/Fenton treatment on lignocellulose degradation in corn stalks. in Book of abstracts VIII International congress Engineering, environment and materials in process industry. 2023;:154.
https://hdl.handle.net/21.15107/rcub_technorep_6344 .

Grbić, Jovana, Mladenović, Dragana, Pavlović, Stefan, Veljović, Đorđe, Lazović, Saša, Đukić-Vuković, Aleksandra, "Effect of combined non-thermal plasma/Fenton treatment on lignocellulose degradation in corn stalks" in Book of abstracts VIII International congress Engineering, environment and materials in process industry (2023):154,
https://hdl.handle.net/21.15107/rcub_technorep_6344 .

TY  - JOUR
AU  - Matić, Tamara
AU  - Ležaja Zebić, Maja
AU  - Miletić, Vesna
AU  - Trajković, Isaak
AU  - Milošević, Miloš
AU  - Racić, Aleksandar
AU  - Veljović, Đorđe
PY  - 2023
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6659
AB  - This study aimed to (1) comparatively analyze properties of Sr- and Mg-substituted
hydroxyapatite (HAP)-based dental inserts; (2) evaluate insert bonding to restorative
materials, and (3) evaluate the effect of doped HAP inserts on fracture resistance
(FR) of human molars with large occlusal restorations. By ion-doping with Sr or Mg,
3 insert types were obtained and characterized using XRD, SEM, Vickers hardness and
fracture toughness. Shear bond strength (SBS) was determined between acid etched or
unetched inserts and following materials: Maxcem cement (Kerr); Filtek Z250
(3M) bonded with Single Bond Universal (SBU; 3M) or Clearfil Universal (Cf; Kuraray).
Modified Class I cavities were prepared in 16 intact molars and restored using insert
+ composite or composite only (control) (n = 8/group). FR of restored molars was
determined by static load until fracture upon thermal cycling. Fracture toughness was
similar between Sr/Mg-doped inserts (0.94–1.04 MPam 1/2 p = .429). Mg-doped
inserts showed greater hardness (range 4.78–5.15 GPa) than Sr6 inserts (3.74
± 0.31 GPa; p < .05). SBS for SBU and Cf adhesives (range 7.19–15.93 MPa) was higher
than for Maxcem (range 3.07–5.95 MPa) (p < .05). There was no significant difference
in FR between molars restored with insert-containing and control restorations (3.00
± 0.30 kN and 3.22 ± 0.42 kN, respectively; p > .05). HAP-based inserts doped with
Mg/Sr had different composition and mechanical properties. Adhesive bonding to
inserts resulted in greater bond strength than cementation, which may be improved by
insert acid-etching. Ion-doped HAP inserts did not affect FR of restored molars. In conclusion,
HAP-based dental inserts may potentially replace dentin in large cavities, without
affecting fracture resistance of restored teeth.
PB  - Wiley Periodicals LLC.
T2  - Journal of Biomedical Materials Research Part B: Applied Biomaterials
T1  - Hydroxyapatite-based dental inserts: microstructure, mechanical properties, bonding efficiency and fracture resistance of molars with occlusal restorations
DO  - 10.1002/jbm.b.35331
ER  - 

@article{
author = "Matić, Tamara and Ležaja Zebić, Maja and Miletić, Vesna and Trajković, Isaak and Milošević, Miloš and Racić, Aleksandar and Veljović, Đorđe",
year = "2023",
abstract = "This study aimed to (1) comparatively analyze properties of Sr- and Mg-substituted
hydroxyapatite (HAP)-based dental inserts; (2) evaluate insert bonding to restorative
materials, and (3) evaluate the effect of doped HAP inserts on fracture resistance
(FR) of human molars with large occlusal restorations. By ion-doping with Sr or Mg,
3 insert types were obtained and characterized using XRD, SEM, Vickers hardness and
fracture toughness. Shear bond strength (SBS) was determined between acid etched or
unetched inserts and following materials: Maxcem cement (Kerr); Filtek Z250
(3M) bonded with Single Bond Universal (SBU; 3M) or Clearfil Universal (Cf; Kuraray).
Modified Class I cavities were prepared in 16 intact molars and restored using insert
+ composite or composite only (control) (n = 8/group). FR of restored molars was
determined by static load until fracture upon thermal cycling. Fracture toughness was
similar between Sr/Mg-doped inserts (0.94–1.04 MPam 1/2 p = .429). Mg-doped
inserts showed greater hardness (range 4.78–5.15 GPa) than Sr6 inserts (3.74
± 0.31 GPa; p < .05). SBS for SBU and Cf adhesives (range 7.19–15.93 MPa) was higher
than for Maxcem (range 3.07–5.95 MPa) (p < .05). There was no significant difference
in FR between molars restored with insert-containing and control restorations (3.00
± 0.30 kN and 3.22 ± 0.42 kN, respectively; p > .05). HAP-based inserts doped with
Mg/Sr had different composition and mechanical properties. Adhesive bonding to
inserts resulted in greater bond strength than cementation, which may be improved by
insert acid-etching. Ion-doped HAP inserts did not affect FR of restored molars. In conclusion,
HAP-based dental inserts may potentially replace dentin in large cavities, without
affecting fracture resistance of restored teeth.",
publisher = "Wiley Periodicals LLC.",
journal = "Journal of Biomedical Materials Research Part B: Applied Biomaterials",
title = "Hydroxyapatite-based dental inserts: microstructure, mechanical properties, bonding efficiency and fracture resistance of molars with occlusal restorations",
doi = "10.1002/jbm.b.35331"
}

Matić, T., Ležaja Zebić, M., Miletić, V., Trajković, I., Milošević, M., Racić, A.,& Veljović, Đ.. (2023). Hydroxyapatite-based dental inserts: microstructure, mechanical properties, bonding efficiency and fracture resistance of molars with occlusal restorations. in Journal of Biomedical Materials Research Part B: Applied Biomaterials
Wiley Periodicals LLC...
https://doi.org/10.1002/jbm.b.35331

Matić T, Ležaja Zebić M, Miletić V, Trajković I, Milošević M, Racić A, Veljović Đ. Hydroxyapatite-based dental inserts: microstructure, mechanical properties, bonding efficiency and fracture resistance of molars with occlusal restorations. in Journal of Biomedical Materials Research Part B: Applied Biomaterials. 2023;.
doi:10.1002/jbm.b.35331 .

Matić, Tamara, Ležaja Zebić, Maja, Miletić, Vesna, Trajković, Isaak, Milošević, Miloš, Racić, Aleksandar, Veljović, Đorđe, "Hydroxyapatite-based dental inserts: microstructure, mechanical properties, bonding efficiency and fracture resistance of molars with occlusal restorations" in Journal of Biomedical Materials Research Part B: Applied Biomaterials (2023),
https://doi.org/10.1002/jbm.b.35331 . .

TY  - CONF
AU  - Stanisavljević, Jelena
AU  - Matić, Tamara
AU  - Baščarević, Zvezdana
AU  - Veljović, Đorđe
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6683
PB  - Belgrade : Serbian Chemical Society
PB  - Belgrade : Serbian Young Chemists Club
C3  - Book of abstracts / 8th Conference of the Young Chemists of Serbia, [Belgrade], 29th October
T1  - Development of controlled-porous bioceramic materials based on calcium-phosphate, doped with magnesium, strontium and fluorine ions in the form of inserts
SP  - 86
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6683
ER  - 

@conference{
author = "Stanisavljević, Jelena and Matić, Tamara and Baščarević, Zvezdana and Veljović, Đorđe",
year = "2022",
publisher = "Belgrade : Serbian Chemical Society, Belgrade : Serbian Young Chemists Club",
journal = "Book of abstracts / 8th Conference of the Young Chemists of Serbia, [Belgrade], 29th October",
title = "Development of controlled-porous bioceramic materials based on calcium-phosphate, doped with magnesium, strontium and fluorine ions in the form of inserts",
pages = "86",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6683"
}

Stanisavljević, J., Matić, T., Baščarević, Z.,& Veljović, Đ.. (2022). Development of controlled-porous bioceramic materials based on calcium-phosphate, doped with magnesium, strontium and fluorine ions in the form of inserts. in Book of abstracts / 8th Conference of the Young Chemists of Serbia, [Belgrade], 29th October
Belgrade : Serbian Chemical Society., 86.
https://hdl.handle.net/21.15107/rcub_technorep_6683

Stanisavljević J, Matić T, Baščarević Z, Veljović Đ. Development of controlled-porous bioceramic materials based on calcium-phosphate, doped with magnesium, strontium and fluorine ions in the form of inserts. in Book of abstracts / 8th Conference of the Young Chemists of Serbia, [Belgrade], 29th October. 2022;:86.
https://hdl.handle.net/21.15107/rcub_technorep_6683 .

Stanisavljević, Jelena, Matić, Tamara, Baščarević, Zvezdana, Veljović, Đorđe, "Development of controlled-porous bioceramic materials based on calcium-phosphate, doped with magnesium, strontium and fluorine ions in the form of inserts" in Book of abstracts / 8th Conference of the Young Chemists of Serbia, [Belgrade], 29th October (2022):86,
https://hdl.handle.net/21.15107/rcub_technorep_6683 .

TY  - CONF
AU  - Ugrinović, Vukašin
AU  - Hristara, Veroniki
AU  - Marković, Maja
AU  - Petrović, Predrag
AU  - Petrović, Rada
AU  - Janaćković, Đorđe
AU  - Veljović, Đorđe
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5240
AB  - Hydrogels are three-dimensional hydrophilic networks of polymers capable of retaining large
amounts of water or biological fluids, which makes them attractive for biomedical and
pharmaceutical applications. Although various types of polymers have been investigated as
hydrogels for biomedical purposes, those obtained from natural polymers have intrinsic
advantages as they are abundant, cheap, biocompatible and biodegradable. Gelatin is a natural
polymer that has been applied in biomedicine due to its low price, biocompatibility, and
biodegradability. HPMC, a derivative of cellulose, is a hydrophilic, biodegradable, and
biocompatible polymer. However, natural polymer-based hydrogels have low mechanical
properties and are relatively soluble in physiological conditions, which requires creative crosslinking strategies to improve the functionality of the hydrogels. The citric acid (CA) is an
inexpensive and non-toxic compound that has been proven to be an effective crosslinker for
natural polymers. In addition, the incorporation of bioactive calcium phosphate particles could
further improve mechanical properties and add new functionalities to the hydrogels.
In this work, we present novel composite hydrogels for biomedical applications, based on CAcrosslinked gelatin/HPMC (HPMC-G) matrix and Mg-doped biphasic calcium phosphate filler
(BCP). Firstly, the HPMC-G hydrogels crosslinking conditions were optimized. Different CA
concentrations, curing temperatures (140-180°C) and times (3-9 min) were applied. During the
second step, the optimaly crosslinked HPMC-G hydrogel was incorporated with different amounts
of BCP. BCP was obtained by calcination of Mg-doped hydroxyapatite (HA) powder synthesized
by the hydrothermal method. XRD analysis confirmed that powder was constituted only of HA
and beta-tricalcium phosphate. The obtained composite hydrogels were characterized by
mechanical testing, FTIR, SEM, swelling behavior and drug deliverability.
PB  - Materials Research Society of Serbia, Belgrade, Serbia
C3  - TWENTY THIRD ANNUAL CONFERENCE - YUCOMAT 2022, Herceg Novi, Montenegro
T1  - Composite hydrogels based on gelatin, hydroxypropyl methylcellulose and Mg-doped biphasic calcium phosphate for biomedical applications
UR  - https://hdl.handle.net/21.15107/rcub_technorep_5240
ER  - 

@conference{
author = "Ugrinović, Vukašin and Hristara, Veroniki and Marković, Maja and Petrović, Predrag and Petrović, Rada and Janaćković, Đorđe and Veljović, Đorđe",
year = "2022",
abstract = "Hydrogels are three-dimensional hydrophilic networks of polymers capable of retaining large
amounts of water or biological fluids, which makes them attractive for biomedical and
pharmaceutical applications. Although various types of polymers have been investigated as
hydrogels for biomedical purposes, those obtained from natural polymers have intrinsic
advantages as they are abundant, cheap, biocompatible and biodegradable. Gelatin is a natural
polymer that has been applied in biomedicine due to its low price, biocompatibility, and
biodegradability. HPMC, a derivative of cellulose, is a hydrophilic, biodegradable, and
biocompatible polymer. However, natural polymer-based hydrogels have low mechanical
properties and are relatively soluble in physiological conditions, which requires creative crosslinking strategies to improve the functionality of the hydrogels. The citric acid (CA) is an
inexpensive and non-toxic compound that has been proven to be an effective crosslinker for
natural polymers. In addition, the incorporation of bioactive calcium phosphate particles could
further improve mechanical properties and add new functionalities to the hydrogels.
In this work, we present novel composite hydrogels for biomedical applications, based on CAcrosslinked gelatin/HPMC (HPMC-G) matrix and Mg-doped biphasic calcium phosphate filler
(BCP). Firstly, the HPMC-G hydrogels crosslinking conditions were optimized. Different CA
concentrations, curing temperatures (140-180°C) and times (3-9 min) were applied. During the
second step, the optimaly crosslinked HPMC-G hydrogel was incorporated with different amounts
of BCP. BCP was obtained by calcination of Mg-doped hydroxyapatite (HA) powder synthesized
by the hydrothermal method. XRD analysis confirmed that powder was constituted only of HA
and beta-tricalcium phosphate. The obtained composite hydrogels were characterized by
mechanical testing, FTIR, SEM, swelling behavior and drug deliverability.",
publisher = "Materials Research Society of Serbia, Belgrade, Serbia",
journal = "TWENTY THIRD ANNUAL CONFERENCE - YUCOMAT 2022, Herceg Novi, Montenegro",
title = "Composite hydrogels based on gelatin, hydroxypropyl methylcellulose and Mg-doped biphasic calcium phosphate for biomedical applications",
url = "https://hdl.handle.net/21.15107/rcub_technorep_5240"
}

Ugrinović, V., Hristara, V., Marković, M., Petrović, P., Petrović, R., Janaćković, Đ.,& Veljović, Đ.. (2022). Composite hydrogels based on gelatin, hydroxypropyl methylcellulose and Mg-doped biphasic calcium phosphate for biomedical applications. in TWENTY THIRD ANNUAL CONFERENCE - YUCOMAT 2022, Herceg Novi, Montenegro
Materials Research Society of Serbia, Belgrade, Serbia..
https://hdl.handle.net/21.15107/rcub_technorep_5240

Ugrinović V, Hristara V, Marković M, Petrović P, Petrović R, Janaćković Đ, Veljović Đ. Composite hydrogels based on gelatin, hydroxypropyl methylcellulose and Mg-doped biphasic calcium phosphate for biomedical applications. in TWENTY THIRD ANNUAL CONFERENCE - YUCOMAT 2022, Herceg Novi, Montenegro. 2022;.
https://hdl.handle.net/21.15107/rcub_technorep_5240 .

Ugrinović, Vukašin, Hristara, Veroniki, Marković, Maja, Petrović, Predrag, Petrović, Rada, Janaćković, Đorđe, Veljović, Đorđe, "Composite hydrogels based on gelatin, hydroxypropyl methylcellulose and Mg-doped biphasic calcium phosphate for biomedical applications" in TWENTY THIRD ANNUAL CONFERENCE - YUCOMAT 2022, Herceg Novi, Montenegro (2022),
https://hdl.handle.net/21.15107/rcub_technorep_5240 .

TY  - JOUR
AU  - Matić, Tamara
AU  - Zebić, M. Ležaja
AU  - Miletić, Vesna
AU  - Cvijović-Alagić, Ivana
AU  - Petrović, Rada
AU  - Janaćković, Đorđe
AU  - Veljović, Đorđe
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5362
AB  - The aim of this study was to investigate the influence of binary Sr, Mg ion-doping compared to the single-ion doping effects on the phase composition and morphology of hydrothermally obtained calcium hydroxyapatite (HAP) powders and on the phase composition, microstructure, and mechanical properties of the sintered materials. Additionally, the focus of this study was to investigate the possible utilization of the binary doped Sr,Mg-HAP compacts as dentin substitutes in restorative dentistry by evaluating their bonding ability with commercially available restorative materials using the shear bond strength test (SBS). The hydrothermally obtained mono-doped Mg5 and Sr5 showed the monophasic apatite structure, while in all co-doped samples β-TCP phase was formed, resulting in biphasic calcium phosphate (BCP) powders. It was confirmed that co-doping with Sr and Mg ions led to the thermal stabilization of the β-TCP phase by suppressing the phase transition into α-TCP when sintered at 1200 °C. Moreover, the co-presence of Mg ions significantly improved the hardness of Sr-doped HAP from 3.74 to 5.02 GPa. Sr,Mg-HAP dental inserts were found to achieve sufficient bonding (13.53 MPa) through the micromechanical interlocking with Z250 dental composite and Single Bond Universal dental adhesive applied with a total etch approach. The SBS values obtained for the SrMg-HAP insert were similar to the literature data on bonding ability with human dentin, indicating that binary doped Sr,Mg-HAP ceramics present a promising material for application in restorative dentistry as dentin substitutes.
T2  - Ceramics International
T1  - Sr,Mg co-doping of calcium hydroxyapatite: Hydrothermal synthesis, processing, characterization and possible application as dentin substitutes
EP  - 11165
IS  - 8
SP  - 11155
VL  - 48
DO  - 10.1016/j.ceramint.2021.12.335
ER  - 

@article{
author = "Matić, Tamara and Zebić, M. Ležaja and Miletić, Vesna and Cvijović-Alagić, Ivana and Petrović, Rada and Janaćković, Đorđe and Veljović, Đorđe",
year = "2022",
abstract = "The aim of this study was to investigate the influence of binary Sr, Mg ion-doping compared to the single-ion doping effects on the phase composition and morphology of hydrothermally obtained calcium hydroxyapatite (HAP) powders and on the phase composition, microstructure, and mechanical properties of the sintered materials. Additionally, the focus of this study was to investigate the possible utilization of the binary doped Sr,Mg-HAP compacts as dentin substitutes in restorative dentistry by evaluating their bonding ability with commercially available restorative materials using the shear bond strength test (SBS). The hydrothermally obtained mono-doped Mg5 and Sr5 showed the monophasic apatite structure, while in all co-doped samples β-TCP phase was formed, resulting in biphasic calcium phosphate (BCP) powders. It was confirmed that co-doping with Sr and Mg ions led to the thermal stabilization of the β-TCP phase by suppressing the phase transition into α-TCP when sintered at 1200 °C. Moreover, the co-presence of Mg ions significantly improved the hardness of Sr-doped HAP from 3.74 to 5.02 GPa. Sr,Mg-HAP dental inserts were found to achieve sufficient bonding (13.53 MPa) through the micromechanical interlocking with Z250 dental composite and Single Bond Universal dental adhesive applied with a total etch approach. The SBS values obtained for the SrMg-HAP insert were similar to the literature data on bonding ability with human dentin, indicating that binary doped Sr,Mg-HAP ceramics present a promising material for application in restorative dentistry as dentin substitutes.",
journal = "Ceramics International",
title = "Sr,Mg co-doping of calcium hydroxyapatite: Hydrothermal synthesis, processing, characterization and possible application as dentin substitutes",
pages = "11165-11155",
number = "8",
volume = "48",
doi = "10.1016/j.ceramint.2021.12.335"
}

Matić, T., Zebić, M. L., Miletić, V., Cvijović-Alagić, I., Petrović, R., Janaćković, Đ.,& Veljović, Đ.. (2022). Sr,Mg co-doping of calcium hydroxyapatite: Hydrothermal synthesis, processing, characterization and possible application as dentin substitutes. in Ceramics International, 48(8), 11155-11165.
https://doi.org/10.1016/j.ceramint.2021.12.335

Matić T, Zebić ML, Miletić V, Cvijović-Alagić I, Petrović R, Janaćković Đ, Veljović Đ. Sr,Mg co-doping of calcium hydroxyapatite: Hydrothermal synthesis, processing, characterization and possible application as dentin substitutes. in Ceramics International. 2022;48(8):11155-11165.
doi:10.1016/j.ceramint.2021.12.335 .

Matić, Tamara, Zebić, M. Ležaja, Miletić, Vesna, Cvijović-Alagić, Ivana, Petrović, Rada, Janaćković, Đorđe, Veljović, Đorđe, "Sr,Mg co-doping of calcium hydroxyapatite: Hydrothermal synthesis, processing, characterization and possible application as dentin substitutes" in Ceramics International, 48, no. 8 (2022):11155-11165,
https://doi.org/10.1016/j.ceramint.2021.12.335 . .

TY  - CONF
AU  - Matić, Tamara
AU  - Zebić, Maja L.
AU  - Miletić, Vesna
AU  - Petrović, Rada
AU  - Janaćković, Đorđe
AU  - Veljović, Đorđe
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6674
AB  - Tooth caries presents one of the most common diseases worldwide, and its treatment involves
removal of the decayed tooth structure, and the cavity restoration using restorative dental materials. Resin based composites (RBCs) are the most commonly used restorative material in practice owing to their great aesthetic appearance allowing the clinicians to adapt the nuance of the restoration to the patient’s tooth color. However, the RBCs harden by the polymerization of monomers that leads to the polymerization shrinkage of the restoration, leaving the micro-gaps at the teeth-restorations interface which allows the secondary caries formation.
PB  - Belgrade : Serbian Academy of Sciences and Arts
C3  - Program & Book of Abstracts / Second International Conference on Electron Microscopy of Nanostructures ELMINA 2022, August 22nd-26th Belgrade, Serbia
T1  - Hydroxyapatite-based Bioceramic Dental Inserts as Dentin Substitute
EP  - 151
SP  - 150
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6674
ER  - 

@conference{
author = "Matić, Tamara and Zebić, Maja L. and Miletić, Vesna and Petrović, Rada and Janaćković, Đorđe and Veljović, Đorđe",
year = "2022",
abstract = "Tooth caries presents one of the most common diseases worldwide, and its treatment involves
removal of the decayed tooth structure, and the cavity restoration using restorative dental materials. Resin based composites (RBCs) are the most commonly used restorative material in practice owing to their great aesthetic appearance allowing the clinicians to adapt the nuance of the restoration to the patient’s tooth color. However, the RBCs harden by the polymerization of monomers that leads to the polymerization shrinkage of the restoration, leaving the micro-gaps at the teeth-restorations interface which allows the secondary caries formation.",
publisher = "Belgrade : Serbian Academy of Sciences and Arts",
journal = "Program & Book of Abstracts / Second International Conference on Electron Microscopy of Nanostructures ELMINA 2022, August 22nd-26th Belgrade, Serbia",
title = "Hydroxyapatite-based Bioceramic Dental Inserts as Dentin Substitute",
pages = "151-150",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6674"
}

Matić, T., Zebić, M. L., Miletić, V., Petrović, R., Janaćković, Đ.,& Veljović, Đ.. (2022). Hydroxyapatite-based Bioceramic Dental Inserts as Dentin Substitute. in Program & Book of Abstracts / Second International Conference on Electron Microscopy of Nanostructures ELMINA 2022, August 22nd-26th Belgrade, Serbia
Belgrade : Serbian Academy of Sciences and Arts., 150-151.
https://hdl.handle.net/21.15107/rcub_technorep_6674

Matić T, Zebić ML, Miletić V, Petrović R, Janaćković Đ, Veljović Đ. Hydroxyapatite-based Bioceramic Dental Inserts as Dentin Substitute. in Program & Book of Abstracts / Second International Conference on Electron Microscopy of Nanostructures ELMINA 2022, August 22nd-26th Belgrade, Serbia. 2022;:150-151.
https://hdl.handle.net/21.15107/rcub_technorep_6674 .

Matić, Tamara, Zebić, Maja L., Miletić, Vesna, Petrović, Rada, Janaćković, Đorđe, Veljović, Đorđe, "Hydroxyapatite-based Bioceramic Dental Inserts as Dentin Substitute" in Program & Book of Abstracts / Second International Conference on Electron Microscopy of Nanostructures ELMINA 2022, August 22nd-26th Belgrade, Serbia (2022):150-151,
https://hdl.handle.net/21.15107/rcub_technorep_6674 .

TY  - CONF
AU  - Matić, Tamara
AU  - Zebić, Maja L.
AU  - Miletić, Vesna
AU  - Petrović, Rada
AU  - Janaćković, Đorđe
AU  - Veljović, Đorđe
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6680
PB  - Belgrade : Institut za multidisciplinarna istraživanja
C3  - Programme and the Book of Abstracts / 6th Conference of The Serbian Society for Ceramic Materials, 6CSCS-2022, June 28-29, 2022, Belgrade, Serbia
T1  - THE INFLUENCE OF HYDROTHERMAL SYNTHESIS TEMPERATURE OF MAGNESIUM DOPED HYDROXYAPATITE ON ITS APPLICATION AS DENTIN SUBSTITUTE
EP  - 37
SP  - 36
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6680
ER  - 

@conference{
author = "Matić, Tamara and Zebić, Maja L. and Miletić, Vesna and Petrović, Rada and Janaćković, Đorđe and Veljović, Đorđe",
year = "2022",
publisher = "Belgrade : Institut za multidisciplinarna istraživanja",
journal = "Programme and the Book of Abstracts / 6th Conference of The Serbian Society for Ceramic Materials, 6CSCS-2022, June 28-29, 2022, Belgrade, Serbia",
title = "THE INFLUENCE OF HYDROTHERMAL SYNTHESIS TEMPERATURE OF MAGNESIUM DOPED HYDROXYAPATITE ON ITS APPLICATION AS DENTIN SUBSTITUTE",
pages = "37-36",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6680"
}

Matić, T., Zebić, M. L., Miletić, V., Petrović, R., Janaćković, Đ.,& Veljović, Đ.. (2022). THE INFLUENCE OF HYDROTHERMAL SYNTHESIS TEMPERATURE OF MAGNESIUM DOPED HYDROXYAPATITE ON ITS APPLICATION AS DENTIN SUBSTITUTE. in Programme and the Book of Abstracts / 6th Conference of The Serbian Society for Ceramic Materials, 6CSCS-2022, June 28-29, 2022, Belgrade, Serbia
Belgrade : Institut za multidisciplinarna istraživanja., 36-37.
https://hdl.handle.net/21.15107/rcub_technorep_6680

Matić T, Zebić ML, Miletić V, Petrović R, Janaćković Đ, Veljović Đ. THE INFLUENCE OF HYDROTHERMAL SYNTHESIS TEMPERATURE OF MAGNESIUM DOPED HYDROXYAPATITE ON ITS APPLICATION AS DENTIN SUBSTITUTE. in Programme and the Book of Abstracts / 6th Conference of The Serbian Society for Ceramic Materials, 6CSCS-2022, June 28-29, 2022, Belgrade, Serbia. 2022;:36-37.
https://hdl.handle.net/21.15107/rcub_technorep_6680 .

Matić, Tamara, Zebić, Maja L., Miletić, Vesna, Petrović, Rada, Janaćković, Đorđe, Veljović, Đorđe, "THE INFLUENCE OF HYDROTHERMAL SYNTHESIS TEMPERATURE OF MAGNESIUM DOPED HYDROXYAPATITE ON ITS APPLICATION AS DENTIN SUBSTITUTE" in Programme and the Book of Abstracts / 6th Conference of The Serbian Society for Ceramic Materials, 6CSCS-2022, June 28-29, 2022, Belgrade, Serbia (2022):36-37,
https://hdl.handle.net/21.15107/rcub_technorep_6680 .

TY  - CONF
AU  - Obradović, Bojana
AU  - Stojkovska, Jasmina
AU  - Radovanović, Željko
AU  - Matić, Tamara
AU  - Petrović, Rada
AU  - Janaćković, Đorđe
AU  - Veljović, Đorđe
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6682
AB  - Biomaterials engineering is one of the strongest research areas at the Faculty of Technology and Metallurgy (FTM), University of Belgrade including development of novel biomaterials for orthopaedic and dental applications. Especially, synthesis and physico-chemical characterization methods are well established resulting in variety of novel inorganic, polymer and composite biomaterials produced in different forms with controlled compositions and structures. Still, expertise in further advancement of the research results towards utilization in medical devices is lacking. The ExcellMater Horizon 2020 project aims to further advance the scientific and technological capacity of the Faculty in this area by twinning the knowledge from the three European partners, internationally leading institutions, with recognized expertise in biological characterization methods, intellectual property protection and utilization, evaluation of health technologies and regulatory aspects of medical devices. The aim of the project is also to increase visibility of scientific research and enhance collaboration of engineers at FTM with life scientists, medical doctors and pharmacists as well as with industry. Here, we will present some of the novel bioceramic and composite biomaterials developed at FTM aimed for potential applications in orthopaedics, dentistry, bone tissue engineering, and cancer research.
PB  - Consiglio Nazionale delle Ricerche Istituto di Struttura della Materia
C3  - Conference proceedings / 3rd biennial International Conference: Biomaterials and novel technologies for healthcare BIOMAH, October 18-21, 2022 Rome – Italy
T1  - The ExcellMater project for advancement of novel bioceramic and composite biomaterials for medical applications
EP  - 197
SP  - 196
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6682
ER  - 

@conference{
author = "Obradović, Bojana and Stojkovska, Jasmina and Radovanović, Željko and Matić, Tamara and Petrović, Rada and Janaćković, Đorđe and Veljović, Đorđe",
year = "2022",
abstract = "Biomaterials engineering is one of the strongest research areas at the Faculty of Technology and Metallurgy (FTM), University of Belgrade including development of novel biomaterials for orthopaedic and dental applications. Especially, synthesis and physico-chemical characterization methods are well established resulting in variety of novel inorganic, polymer and composite biomaterials produced in different forms with controlled compositions and structures. Still, expertise in further advancement of the research results towards utilization in medical devices is lacking. The ExcellMater Horizon 2020 project aims to further advance the scientific and technological capacity of the Faculty in this area by twinning the knowledge from the three European partners, internationally leading institutions, with recognized expertise in biological characterization methods, intellectual property protection and utilization, evaluation of health technologies and regulatory aspects of medical devices. The aim of the project is also to increase visibility of scientific research and enhance collaboration of engineers at FTM with life scientists, medical doctors and pharmacists as well as with industry. Here, we will present some of the novel bioceramic and composite biomaterials developed at FTM aimed for potential applications in orthopaedics, dentistry, bone tissue engineering, and cancer research.",
publisher = "Consiglio Nazionale delle Ricerche Istituto di Struttura della Materia",
journal = "Conference proceedings / 3rd biennial International Conference: Biomaterials and novel technologies for healthcare BIOMAH, October 18-21, 2022 Rome – Italy",
title = "The ExcellMater project for advancement of novel bioceramic and composite biomaterials for medical applications",
pages = "197-196",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6682"
}

Obradović, B., Stojkovska, J., Radovanović, Ž., Matić, T., Petrović, R., Janaćković, Đ.,& Veljović, Đ.. (2022). The ExcellMater project for advancement of novel bioceramic and composite biomaterials for medical applications. in Conference proceedings / 3rd biennial International Conference: Biomaterials and novel technologies for healthcare BIOMAH, October 18-21, 2022 Rome – Italy
Consiglio Nazionale delle Ricerche Istituto di Struttura della Materia., 196-197.
https://hdl.handle.net/21.15107/rcub_technorep_6682

Obradović B, Stojkovska J, Radovanović Ž, Matić T, Petrović R, Janaćković Đ, Veljović Đ. The ExcellMater project for advancement of novel bioceramic and composite biomaterials for medical applications. in Conference proceedings / 3rd biennial International Conference: Biomaterials and novel technologies for healthcare BIOMAH, October 18-21, 2022 Rome – Italy. 2022;:196-197.
https://hdl.handle.net/21.15107/rcub_technorep_6682 .

Obradović, Bojana, Stojkovska, Jasmina, Radovanović, Željko, Matić, Tamara, Petrović, Rada, Janaćković, Đorđe, Veljović, Đorđe, "The ExcellMater project for advancement of novel bioceramic and composite biomaterials for medical applications" in Conference proceedings / 3rd biennial International Conference: Biomaterials and novel technologies for healthcare BIOMAH, October 18-21, 2022 Rome – Italy (2022):196-197,
https://hdl.handle.net/21.15107/rcub_technorep_6682 .

TY  - JOUR
AU  - Ugrinović, Vukašin
AU  - Panić, Vesna
AU  - Spasojević, Pavle
AU  - Seslija, Sanja
AU  - Bozic, Bojan
AU  - Petrović, Rada
AU  - Janaćković, Đorđe
AU  - Veljović, Đorđe
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4984
AB  - Hydrogels are promising materials for biomedical applications due to highly hydrated, porous, permeable structure with possibility to accommodate living cells, drugs, or bioactive factors. In this paper, we reported poly(methacrylic acid) (PMAA)/gelatin IPN hydrogels, synthesized by free-radical polymerization, with adjustable mechanical, structural, physicochemical, and biological characteristics. The influence of methacrylic acid (MAA), gelatin, and cross-linker in the precursor solution on hydrogels properties was investigated. The increasing concentration of MAA, gelatin, and cross-linker led to better mechanical properties, lower porosity, and water content. The compressive mechanical properties of hydrogels were significantly better in comparison to a single-network PMAA hydrogel, while the obtained compressive strength values up to 16 MPa were comparable with tough hydrogels. The increasing concentration of MAA and cross-linker reduced fatigue resistance and degradability, while the increase in gelatin content acted in the opposite way. Swelling tests in different pH conditions demonstrated strong pH-sensibility of the hydrogels, which was more pronounced as MAA concentration was higher, and gelatin and cross-linker concentrations were lower. In addition, the hydrogels strongly promoted the proliferation of human periodontal ligament stem cells and MRC-5 cells as assayed by MTT assay.
T2  - Polymer Engineering and Science
T1  - Strong and tough, pH sensible, interpenetrating network hydrogels based on gelatin and poly(methacrylic acid)
DO  - 10.1002/pen.25870
ER  - 

@article{
author = "Ugrinović, Vukašin and Panić, Vesna and Spasojević, Pavle and Seslija, Sanja and Bozic, Bojan and Petrović, Rada and Janaćković, Đorđe and Veljović, Đorđe",
year = "2022",
abstract = "Hydrogels are promising materials for biomedical applications due to highly hydrated, porous, permeable structure with possibility to accommodate living cells, drugs, or bioactive factors. In this paper, we reported poly(methacrylic acid) (PMAA)/gelatin IPN hydrogels, synthesized by free-radical polymerization, with adjustable mechanical, structural, physicochemical, and biological characteristics. The influence of methacrylic acid (MAA), gelatin, and cross-linker in the precursor solution on hydrogels properties was investigated. The increasing concentration of MAA, gelatin, and cross-linker led to better mechanical properties, lower porosity, and water content. The compressive mechanical properties of hydrogels were significantly better in comparison to a single-network PMAA hydrogel, while the obtained compressive strength values up to 16 MPa were comparable with tough hydrogels. The increasing concentration of MAA and cross-linker reduced fatigue resistance and degradability, while the increase in gelatin content acted in the opposite way. Swelling tests in different pH conditions demonstrated strong pH-sensibility of the hydrogels, which was more pronounced as MAA concentration was higher, and gelatin and cross-linker concentrations were lower. In addition, the hydrogels strongly promoted the proliferation of human periodontal ligament stem cells and MRC-5 cells as assayed by MTT assay.",
journal = "Polymer Engineering and Science",
title = "Strong and tough, pH sensible, interpenetrating network hydrogels based on gelatin and poly(methacrylic acid)",
doi = "10.1002/pen.25870"
}

Ugrinović, V., Panić, V., Spasojević, P., Seslija, S., Bozic, B., Petrović, R., Janaćković, Đ.,& Veljović, Đ.. (2022). Strong and tough, pH sensible, interpenetrating network hydrogels based on gelatin and poly(methacrylic acid). in Polymer Engineering and Science.
https://doi.org/10.1002/pen.25870

Ugrinović V, Panić V, Spasojević P, Seslija S, Bozic B, Petrović R, Janaćković Đ, Veljović Đ. Strong and tough, pH sensible, interpenetrating network hydrogels based on gelatin and poly(methacrylic acid). in Polymer Engineering and Science. 2022;.
doi:10.1002/pen.25870 .

Ugrinović, Vukašin, Panić, Vesna, Spasojević, Pavle, Seslija, Sanja, Bozic, Bojan, Petrović, Rada, Janaćković, Đorđe, Veljović, Đorđe, "Strong and tough, pH sensible, interpenetrating network hydrogels based on gelatin and poly(methacrylic acid)" in Polymer Engineering and Science (2022),
https://doi.org/10.1002/pen.25870 . .

TY  - CONF
AU  - Laketić, Slađana
AU  - Rakin, Marko
AU  - Momčilović, Miloš
AU  - Ciganović, Jovan
AU  - Veljović, Đorđe
AU  - Cvijović, Ivana
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6009
AB  - Titanium alloys are finding increasing use as biomaterials due to their low elastic modulus and high damage tolerance. However, the somewhat inadequate alloy surface performance can impede their biomedical application. Surface modification methods have been therefore developed to improve the alloys' surface bioactivity and osseointegration. Laser treatment allows the alloy surface to be modified, providing it with new functionalized surface chemistry and morphology, without compromising the rest of the material properties. Thus, the aim of the study was to examine the laser-induced alterations generated on the Ti-45Nb alloy surface by an ultrashort pulsed laser. The obtained results reveal that laser beam interaction with the target material led to the formation of significant alterations in surface morphology. Surface craters, microcracks, and surface features in the form of periodic and rippled structures and solidified droplets can be observed in the irradiated area. Also, it was found that the higher damage degree along with the material depth and the higher surface roughness were achieved during the irradiation in the argon atmosphere due to the formation of the more pronounced morphological changes on the alloy surface that are induced by higher laser ablation. Furthermore, obtained results showed that alloy surface modification in air, argon, and nitrogen atmosphere additionally caused changes in the surface chemical composition. Namely, after irradiation, the presence of oxygen was observed in the central irradiated area indicating the formation of bioactive Ti-oxide surface film with content that varies with the irradiation parameters variation. Therefore, laser beam irradiation can be singled out as the surface modification method for efficient inducement of the specific surface characteristics that can provide titanium alloys with enhanced osseointegration properties.
PB  - Materials Research Society of Serbia – MRS-Serbia
C3  - TWENTY THIRD ANNUAL CONFERENCE - YUCOMAT
T1  - Laser-induced chemical and mophological changes of the titanium alloy surface under different irradiation parameters
SP  - 92
VL  - XLV
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6009
ER  - 

@conference{
author = "Laketić, Slađana and Rakin, Marko and Momčilović, Miloš and Ciganović, Jovan and Veljović, Đorđe and Cvijović, Ivana",
year = "2022",
abstract = "Titanium alloys are finding increasing use as biomaterials due to their low elastic modulus and high damage tolerance. However, the somewhat inadequate alloy surface performance can impede their biomedical application. Surface modification methods have been therefore developed to improve the alloys' surface bioactivity and osseointegration. Laser treatment allows the alloy surface to be modified, providing it with new functionalized surface chemistry and morphology, without compromising the rest of the material properties. Thus, the aim of the study was to examine the laser-induced alterations generated on the Ti-45Nb alloy surface by an ultrashort pulsed laser. The obtained results reveal that laser beam interaction with the target material led to the formation of significant alterations in surface morphology. Surface craters, microcracks, and surface features in the form of periodic and rippled structures and solidified droplets can be observed in the irradiated area. Also, it was found that the higher damage degree along with the material depth and the higher surface roughness were achieved during the irradiation in the argon atmosphere due to the formation of the more pronounced morphological changes on the alloy surface that are induced by higher laser ablation. Furthermore, obtained results showed that alloy surface modification in air, argon, and nitrogen atmosphere additionally caused changes in the surface chemical composition. Namely, after irradiation, the presence of oxygen was observed in the central irradiated area indicating the formation of bioactive Ti-oxide surface film with content that varies with the irradiation parameters variation. Therefore, laser beam irradiation can be singled out as the surface modification method for efficient inducement of the specific surface characteristics that can provide titanium alloys with enhanced osseointegration properties.",
publisher = "Materials Research Society of Serbia – MRS-Serbia",
journal = "TWENTY THIRD ANNUAL CONFERENCE - YUCOMAT",
title = "Laser-induced chemical and mophological changes of the titanium alloy surface under different irradiation parameters",
pages = "92",
volume = "XLV",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6009"
}

Laketić, S., Rakin, M., Momčilović, M., Ciganović, J., Veljović, Đ.,& Cvijović, I.. (2022). Laser-induced chemical and mophological changes of the titanium alloy surface under different irradiation parameters. in TWENTY THIRD ANNUAL CONFERENCE - YUCOMAT
Materials Research Society of Serbia – MRS-Serbia., XLV, 92.
https://hdl.handle.net/21.15107/rcub_technorep_6009

Laketić S, Rakin M, Momčilović M, Ciganović J, Veljović Đ, Cvijović I. Laser-induced chemical and mophological changes of the titanium alloy surface under different irradiation parameters. in TWENTY THIRD ANNUAL CONFERENCE - YUCOMAT. 2022;XLV:92.
https://hdl.handle.net/21.15107/rcub_technorep_6009 .

Laketić, Slađana, Rakin, Marko, Momčilović, Miloš, Ciganović, Jovan, Veljović, Đorđe, Cvijović, Ivana, "Laser-induced chemical and mophological changes of the titanium alloy surface under different irradiation parameters" in TWENTY THIRD ANNUAL CONFERENCE - YUCOMAT, XLV (2022):92,
https://hdl.handle.net/21.15107/rcub_technorep_6009 .

TY  - CONF
AU  - Cvijović-Alagić, Ivana
AU  - Laketić, Slađana
AU  - Momčilović, Miloš
AU  - Ciganović, Jovan
AU  - Veljović, Đorđe
AU  - Rakin, Marko
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/6011
AB  - Hard-tissue replacements are most commonly made from the Ti-based materials, such as
commercially pure titanium (CP-Ti) and Ti-6Al-4V (mass%) alloy, because of their exceptional
biocompatible properties combined with the excellent corrosive and mechanical characteristics [1].
More recently, efforts have been made to additionally enhance the properties of the metallic
implants through the careful selection of the alloy composition and surface modification technics
[2,3]. As a result, second-generation β-type Ti alloys, containing non-toxic elements, have been
developed. One of the promising β-type implant alloys is Ti-13Nb-13Zr (mass%). Even though the
corrosion resistance and mechanical properties of this alloy are improved in comparison to the
commonly used metallic implant materials, its biocompatible and osseointegration properties can
and must be additionally enhanced. For that purpose several surface modification technics can be
used, however, laser irradiation stands out as the most promising one. Because of that scope of the
present research was to investigate the possibility of successful surface modification of the most
commonly used implant material, i.e. CP-Ti, and the second-generation Ti-13Nb-13Zr alloy by
utilizing the easy-to-apply laser irradiation method in order to obtain improved implant tribocorrosive
properties and enhanced biointegration and bioactivity.
Laser surface modifications were conducted using the Nd:YAG system in the air and argon
atmosphere under different laser output energies. Implant materials surface morphologies after the
laser irradiation treatment were investigated using the field-emission scanning electron microscopy
(FE-SEM) and optical profilometry, while the impact of the laser irradiation on the implant
materials surface characteristics were examined using the energy dispersive spectrometry (EDS)
and microhardness measurements.
Conducted research showed that utilization of the Nd:YAG laser irradiation resulted in significant
alterations of the CP-Ti and Ti-13Nb-13Zr alloy surface chemistry, morphology and microhardness.
Laser irradiation of both investigated materials led to the formation of visible microcracks and
hydrodynamic effects in the central part of the irradiated area, while traces of melted and solidified
material were observed at its periphery. More pronounced morphological changes were induced
during the laser irradiation in an argon atmosphere, while a higher degree of texturing was recorded
at the surface of the Ti-13Nb-13Zr alloy. At the irradiated surfaces, the formation of the oxide layer,
predominantly composed of Ti-oxide particles, was detected. Surface oxides are desirable since
their presence can improve the implant material bioactivity with a simultaneous increase of the
tribo-corrosive properties through the formation of the hard corrosion resistance surface film. Laserinduced
chemical and morphological alterations were more distinctive in the case of the Ti-13Nb-
13Zr alloy.
PB  - Vinča Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade
PB  - Serbian Society for Innovative Materials in Extreme Conditions (SIM-EXTREME)
C3  - 1st International Conference on Innovative Materials in Extreme Conditions (IMEC2022)
T1  - Laser irradiation as an easy-to-apply method for Ti-based implant materials enhancement
SP  - 20
UR  - https://hdl.handle.net/21.15107/rcub_technorep_6011
ER  - 

@conference{
author = "Cvijović-Alagić, Ivana and Laketić, Slađana and Momčilović, Miloš and Ciganović, Jovan and Veljović, Đorđe and Rakin, Marko",
year = "2022",
abstract = "Hard-tissue replacements are most commonly made from the Ti-based materials, such as
commercially pure titanium (CP-Ti) and Ti-6Al-4V (mass%) alloy, because of their exceptional
biocompatible properties combined with the excellent corrosive and mechanical characteristics [1].
More recently, efforts have been made to additionally enhance the properties of the metallic
implants through the careful selection of the alloy composition and surface modification technics
[2,3]. As a result, second-generation β-type Ti alloys, containing non-toxic elements, have been
developed. One of the promising β-type implant alloys is Ti-13Nb-13Zr (mass%). Even though the
corrosion resistance and mechanical properties of this alloy are improved in comparison to the
commonly used metallic implant materials, its biocompatible and osseointegration properties can
and must be additionally enhanced. For that purpose several surface modification technics can be
used, however, laser irradiation stands out as the most promising one. Because of that scope of the
present research was to investigate the possibility of successful surface modification of the most
commonly used implant material, i.e. CP-Ti, and the second-generation Ti-13Nb-13Zr alloy by
utilizing the easy-to-apply laser irradiation method in order to obtain improved implant tribocorrosive
properties and enhanced biointegration and bioactivity.
Laser surface modifications were conducted using the Nd:YAG system in the air and argon
atmosphere under different laser output energies. Implant materials surface morphologies after the
laser irradiation treatment were investigated using the field-emission scanning electron microscopy
(FE-SEM) and optical profilometry, while the impact of the laser irradiation on the implant
materials surface characteristics were examined using the energy dispersive spectrometry (EDS)
and microhardness measurements.
Conducted research showed that utilization of the Nd:YAG laser irradiation resulted in significant
alterations of the CP-Ti and Ti-13Nb-13Zr alloy surface chemistry, morphology and microhardness.
Laser irradiation of both investigated materials led to the formation of visible microcracks and
hydrodynamic effects in the central part of the irradiated area, while traces of melted and solidified
material were observed at its periphery. More pronounced morphological changes were induced
during the laser irradiation in an argon atmosphere, while a higher degree of texturing was recorded
at the surface of the Ti-13Nb-13Zr alloy. At the irradiated surfaces, the formation of the oxide layer,
predominantly composed of Ti-oxide particles, was detected. Surface oxides are desirable since
their presence can improve the implant material bioactivity with a simultaneous increase of the
tribo-corrosive properties through the formation of the hard corrosion resistance surface film. Laserinduced
chemical and morphological alterations were more distinctive in the case of the Ti-13Nb-
13Zr alloy.",
publisher = "Vinča Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade, Serbian Society for Innovative Materials in Extreme Conditions (SIM-EXTREME)",
journal = "1st International Conference on Innovative Materials in Extreme Conditions (IMEC2022)",
title = "Laser irradiation as an easy-to-apply method for Ti-based implant materials enhancement",
pages = "20",
url = "https://hdl.handle.net/21.15107/rcub_technorep_6011"
}

Cvijović-Alagić, I., Laketić, S., Momčilović, M., Ciganović, J., Veljović, Đ.,& Rakin, M.. (2022). Laser irradiation as an easy-to-apply method for Ti-based implant materials enhancement. in 1st International Conference on Innovative Materials in Extreme Conditions (IMEC2022)
Vinča Institute of Nuclear Sciences - National Institute of thе Republic of Serbia, University of Belgrade., 20.
https://hdl.handle.net/21.15107/rcub_technorep_6011

Cvijović-Alagić I, Laketić S, Momčilović M, Ciganović J, Veljović Đ, Rakin M. Laser irradiation as an easy-to-apply method for Ti-based implant materials enhancement. in 1st International Conference on Innovative Materials in Extreme Conditions (IMEC2022). 2022;:20.
https://hdl.handle.net/21.15107/rcub_technorep_6011 .

Cvijović-Alagić, Ivana, Laketić, Slađana, Momčilović, Miloš, Ciganović, Jovan, Veljović, Đorđe, Rakin, Marko, "Laser irradiation as an easy-to-apply method for Ti-based implant materials enhancement" in 1st International Conference on Innovative Materials in Extreme Conditions (IMEC2022) (2022):20,
https://hdl.handle.net/21.15107/rcub_technorep_6011 .

TY  - CONF
AU  - Barjaktarević, Dragana
AU  - Rakin, Marko
AU  - Veljović, Đorđe
AU  - Međo, Bojan
AU  - Đokić, Veljko
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5258
AB  - Nanostructured surface of Ti-13Nb-13Zr alloy (coarse-grained (CG), and ultrafine-grained (UFG), obtained by high pressure torsion - HPT) was formed using electrochemical anodization in the 1M H3PO4 + NaF electrolyte, during 30, 60, 90 and 120 minutes. The scanning electron microscopy (SEM) was used to characterise the morphology of the surface, while chemical characterization of the obtained nanostructured surface was performed using energy dispersive spectroscopy (EDS). The surface modulus of elasticity and hardness before and after the surface nanostructure modification, was examined using the nanoindentation test, while the analysis of deformation and damage of the nanostructured surface after nanoindentation was performed using SEM. Cytotoxicity of the tested alloys and cell culture viability were assessed using the tetrazolium salt colorimetric test (MTT test) using mouse fibroblasts (L-929) and human lung fibroblasts (MRC-5) in liquid medium. Morphology and adhesion of cells on the surface were analysed using SEM. The obtained results indicate the strong influence of time, as a parameter of anodization, on the surface morphology. Influence of the HPT processing on the homogeneity of the nanostructured surface obtained by electrochemical anodization has also been shown. The alloys before and after the surface nanostructure modification are adequate in their biocompatibility for use in the implantology. Characterization of the titanium-based materials surface using nanoindentation showed a decrease in the values of modulus of elasticity and hardness for materials with nanostructured surface, which are close to the values of bone tissue in the human body.
PB  - Materials Research Society of Srebia
C3  - Twenty-third Annual Conference YUCOMAT 2022 &
Twelfth World Round Table Conference on Sintering XII WRTCS
T1  - Nanostructured surface modification and characterization of titanium based materials for medical application
SP  - 154
UR  - https://hdl.handle.net/21.15107/rcub_technorep_5258
ER  - 

@conference{
author = "Barjaktarević, Dragana and Rakin, Marko and Veljović, Đorđe and Međo, Bojan and Đokić, Veljko",
year = "2022",
abstract = "Nanostructured surface of Ti-13Nb-13Zr alloy (coarse-grained (CG), and ultrafine-grained (UFG), obtained by high pressure torsion - HPT) was formed using electrochemical anodization in the 1M H3PO4 + NaF electrolyte, during 30, 60, 90 and 120 minutes. The scanning electron microscopy (SEM) was used to characterise the morphology of the surface, while chemical characterization of the obtained nanostructured surface was performed using energy dispersive spectroscopy (EDS). The surface modulus of elasticity and hardness before and after the surface nanostructure modification, was examined using the nanoindentation test, while the analysis of deformation and damage of the nanostructured surface after nanoindentation was performed using SEM. Cytotoxicity of the tested alloys and cell culture viability were assessed using the tetrazolium salt colorimetric test (MTT test) using mouse fibroblasts (L-929) and human lung fibroblasts (MRC-5) in liquid medium. Morphology and adhesion of cells on the surface were analysed using SEM. The obtained results indicate the strong influence of time, as a parameter of anodization, on the surface morphology. Influence of the HPT processing on the homogeneity of the nanostructured surface obtained by electrochemical anodization has also been shown. The alloys before and after the surface nanostructure modification are adequate in their biocompatibility for use in the implantology. Characterization of the titanium-based materials surface using nanoindentation showed a decrease in the values of modulus of elasticity and hardness for materials with nanostructured surface, which are close to the values of bone tissue in the human body.",
publisher = "Materials Research Society of Srebia",
journal = "Twenty-third Annual Conference YUCOMAT 2022 &
Twelfth World Round Table Conference on Sintering XII WRTCS",
title = "Nanostructured surface modification and characterization of titanium based materials for medical application",
pages = "154",
url = "https://hdl.handle.net/21.15107/rcub_technorep_5258"
}

Barjaktarević, D., Rakin, M., Veljović, Đ., Međo, B.,& Đokić, V.. (2022). Nanostructured surface modification and characterization of titanium based materials for medical application. in Twenty-third Annual Conference YUCOMAT 2022 &
Twelfth World Round Table Conference on Sintering XII WRTCS
Materials Research Society of Srebia., 154.
https://hdl.handle.net/21.15107/rcub_technorep_5258

Barjaktarević D, Rakin M, Veljović Đ, Međo B, Đokić V. Nanostructured surface modification and characterization of titanium based materials for medical application. in Twenty-third Annual Conference YUCOMAT 2022 &
Twelfth World Round Table Conference on Sintering XII WRTCS. 2022;:154.
https://hdl.handle.net/21.15107/rcub_technorep_5258 .

Barjaktarević, Dragana, Rakin, Marko, Veljović, Đorđe, Međo, Bojan, Đokić, Veljko, "Nanostructured surface modification and characterization of titanium based materials for medical application" in Twenty-third Annual Conference YUCOMAT 2022 &
Twelfth World Round Table Conference on Sintering XII WRTCS (2022):154,
https://hdl.handle.net/21.15107/rcub_technorep_5258 .

TY  - JOUR
AU  - Pantić, Nevena
AU  - Spasojević, Milica
AU  - Stojanović, Željko
AU  - Veljović, Đorđe
AU  - Krstić, Jugoslav
AU  - Balaž, Ana Marija
AU  - Prodanović, Radivoje
AU  - Prodanović, Olivera
PY  - 2022
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/5096
AB  - Novel macroporous copolymers of glycidyl methacrylate and ethylene glycol dimethacrylate with mean pore size diameters ranging from 150 to 310 nm were synthesized by dispersion polymerization and modified with ethylenediamine. The glutaraldehyde and periodate method were employed to immobilize horseradish peroxidase (HRP) onto these carriers. The activity of the immobilized enzyme was greatly affected by the pore size of the carrier. The highest specific activities of 9.65 and 8.94 U/g of dry weight were obtained for HRP immobilized by the periodate-route onto poly(GMA‐co‐EGDMA) carriers with pore size diameters of 234 and 297 nm, respectively. Stability studies showed an improved operational stability of immobilized peroxidase at 65 °C and in an organic solvent. HRP immobilized on a copolymer with a pore size of 234 nm, showing the highest specific activity and good stability, had higher activities at almost all pH values than the native enzyme and the increased Km value for pyrogallol oxidation. Immobilized HRP retained 80% of its original activity after five consecutive cycles of the pyrogallol oxidation and 98% of its initial activity in a storage stability study. Enzyme immobilized onto the macroporous copolymer with the pore size diameter of 234 nm showed a substantial degree of phenol removal achieved by immobilized peroxidase.
PB  - Springer
T2  - Journal of Polymers and the Environment
T1  - Immobilization of Horseradish Peroxidase on Macroporous Glycidyl-Based Copolymers with Different Surface Characteristics for the Removal of Phenol
DO  - 10.1007/s10924-021-02364-3
ER  - 

@article{
author = "Pantić, Nevena and Spasojević, Milica and Stojanović, Željko and Veljović, Đorđe and Krstić, Jugoslav and Balaž, Ana Marija and Prodanović, Radivoje and Prodanović, Olivera",
year = "2022",
abstract = "Novel macroporous copolymers of glycidyl methacrylate and ethylene glycol dimethacrylate with mean pore size diameters ranging from 150 to 310 nm were synthesized by dispersion polymerization and modified with ethylenediamine. The glutaraldehyde and periodate method were employed to immobilize horseradish peroxidase (HRP) onto these carriers. The activity of the immobilized enzyme was greatly affected by the pore size of the carrier. The highest specific activities of 9.65 and 8.94 U/g of dry weight were obtained for HRP immobilized by the periodate-route onto poly(GMA‐co‐EGDMA) carriers with pore size diameters of 234 and 297 nm, respectively. Stability studies showed an improved operational stability of immobilized peroxidase at 65 °C and in an organic solvent. HRP immobilized on a copolymer with a pore size of 234 nm, showing the highest specific activity and good stability, had higher activities at almost all pH values than the native enzyme and the increased Km value for pyrogallol oxidation. Immobilized HRP retained 80% of its original activity after five consecutive cycles of the pyrogallol oxidation and 98% of its initial activity in a storage stability study. Enzyme immobilized onto the macroporous copolymer with the pore size diameter of 234 nm showed a substantial degree of phenol removal achieved by immobilized peroxidase.",
publisher = "Springer",
journal = "Journal of Polymers and the Environment",
title = "Immobilization of Horseradish Peroxidase on Macroporous Glycidyl-Based Copolymers with Different Surface Characteristics for the Removal of Phenol",
doi = "10.1007/s10924-021-02364-3"
}

Pantić, N., Spasojević, M., Stojanović, Ž., Veljović, Đ., Krstić, J., Balaž, A. M., Prodanović, R.,& Prodanović, O.. (2022). Immobilization of Horseradish Peroxidase on Macroporous Glycidyl-Based Copolymers with Different Surface Characteristics for the Removal of Phenol. in Journal of Polymers and the Environment
Springer..
https://doi.org/10.1007/s10924-021-02364-3

Pantić N, Spasojević M, Stojanović Ž, Veljović Đ, Krstić J, Balaž AM, Prodanović R, Prodanović O. Immobilization of Horseradish Peroxidase on Macroporous Glycidyl-Based Copolymers with Different Surface Characteristics for the Removal of Phenol. in Journal of Polymers and the Environment. 2022;.
doi:10.1007/s10924-021-02364-3 .

Pantić, Nevena, Spasojević, Milica, Stojanović, Željko, Veljović, Đorđe, Krstić, Jugoslav, Balaž, Ana Marija, Prodanović, Radivoje, Prodanović, Olivera, "Immobilization of Horseradish Peroxidase on Macroporous Glycidyl-Based Copolymers with Different Surface Characteristics for the Removal of Phenol" in Journal of Polymers and the Environment (2022),
https://doi.org/10.1007/s10924-021-02364-3 . .