TY  - JOUR
AU  - Milosević, Miljan
AU  - Stojanović, Dušica
AU  - Simić, Vladimir
AU  - Grković, Mirjana
AU  - Bjelović, Miloš
AU  - Uskoković, Petar
AU  - Kojić, Miloš
PY  - 2020
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4388
AB  - The authors present the preparation procedure and a computational model of a three-layered fibrous scaffold for prolonged drug release. The scaffold, produced by emulsion/sequential electrospinning, consists of a poly(d,l-lactic-co-glycolic acid) (PLGA) fiber layer sandwiched between two poly(epsilon -caprolactone) (PCL) layers. Experimental results of drug release rates from the scaffold are compared with the results of the recently introduced computational finite element (FE) models for diffusive drug release from nanofibers to the three-dimensional (3D) surrounding medium. Two different FE models are used: (1) a 3D discretized continuum and fibers represented by a simple radial one-dimensional (1D) finite elements, and (2) a 3D continuum discretized by composite smeared finite elements (CSFEs) containing the fiber smeared and surrounding domains. Both models include the effects of polymer degradation and hydrophobicity (as partitioning) of the drug at the fiber/surrounding interface. The CSFE model includes a volumetric fraction of fibers and diameter distribution, and is additionally enhanced by using correction function to improve the accuracy of the model. The computational results are validated on Rhodamine B (fluorescent drug l) and other hydrophilic drugs. Agreement with experimental results proves that numerical models can serve as efficient tools for drug release to the surrounding porous medium or biological tissue. It is demonstrated that the introduced three-layered scaffold delays the drug release process and can be used for the time-controlled release of drugs in postoperative therapy.
PB  - Nature Publishing Group, London
T2  - Scientific Reports
T1  - Preparation and modeling of three-layered PCL/PLGA/PCL fibrous scaffolds for prolonged drug release
IS  - 1
VL  - 10
DO  - 10.1038/s41598-020-68117-9
ER  - 

@article{
author = "Milosević, Miljan and Stojanović, Dušica and Simić, Vladimir and Grković, Mirjana and Bjelović, Miloš and Uskoković, Petar and Kojić, Miloš",
year = "2020",
abstract = "The authors present the preparation procedure and a computational model of a three-layered fibrous scaffold for prolonged drug release. The scaffold, produced by emulsion/sequential electrospinning, consists of a poly(d,l-lactic-co-glycolic acid) (PLGA) fiber layer sandwiched between two poly(epsilon -caprolactone) (PCL) layers. Experimental results of drug release rates from the scaffold are compared with the results of the recently introduced computational finite element (FE) models for diffusive drug release from nanofibers to the three-dimensional (3D) surrounding medium. Two different FE models are used: (1) a 3D discretized continuum and fibers represented by a simple radial one-dimensional (1D) finite elements, and (2) a 3D continuum discretized by composite smeared finite elements (CSFEs) containing the fiber smeared and surrounding domains. Both models include the effects of polymer degradation and hydrophobicity (as partitioning) of the drug at the fiber/surrounding interface. The CSFE model includes a volumetric fraction of fibers and diameter distribution, and is additionally enhanced by using correction function to improve the accuracy of the model. The computational results are validated on Rhodamine B (fluorescent drug l) and other hydrophilic drugs. Agreement with experimental results proves that numerical models can serve as efficient tools for drug release to the surrounding porous medium or biological tissue. It is demonstrated that the introduced three-layered scaffold delays the drug release process and can be used for the time-controlled release of drugs in postoperative therapy.",
publisher = "Nature Publishing Group, London",
journal = "Scientific Reports",
title = "Preparation and modeling of three-layered PCL/PLGA/PCL fibrous scaffolds for prolonged drug release",
number = "1",
volume = "10",
doi = "10.1038/s41598-020-68117-9"
}

Milosević, M., Stojanović, D., Simić, V., Grković, M., Bjelović, M., Uskoković, P.,& Kojić, M.. (2020). Preparation and modeling of three-layered PCL/PLGA/PCL fibrous scaffolds for prolonged drug release. in Scientific Reports
Nature Publishing Group, London., 10(1).
https://doi.org/10.1038/s41598-020-68117-9

Milosević M, Stojanović D, Simić V, Grković M, Bjelović M, Uskoković P, Kojić M. Preparation and modeling of three-layered PCL/PLGA/PCL fibrous scaffolds for prolonged drug release. in Scientific Reports. 2020;10(1).
doi:10.1038/s41598-020-68117-9 .

Milosević, Miljan, Stojanović, Dušica, Simić, Vladimir, Grković, Mirjana, Bjelović, Miloš, Uskoković, Petar, Kojić, Miloš, "Preparation and modeling of three-layered PCL/PLGA/PCL fibrous scaffolds for prolonged drug release" in Scientific Reports, 10, no. 1 (2020),
https://doi.org/10.1038/s41598-020-68117-9 . .

TY  - JOUR
AU  - Grković, Mirjana
AU  - Stojanović, Dušica
AU  - Pavlović, Vladimir B.
AU  - Rajilić-Stojanović, Mirjana
AU  - Bjelović, Miloš
AU  - Uskoković, Petar
PY  - 2017
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3558
AB  - In this study conditions for green crosslinking with citric acid of chitosan/PEO (polyethylene oxide) nanofibers were evaluated. The thermal in situ crosslinking enabled penetration of crosslinking agent into the matrix providing an improvement of antibacterial activity, thermal stability and mechanical properties of the prepared material. With an increase of temperature above 80 degrees C antibacterial activity against Staphylococcus aureus and Escherichia coil, inversely decreased. Moreover crosslinking provided prolonged controlled drug release with outstanding increase of mechanical properties observed by nanoindentation measurements. Results of the investigation indicated crosslinking as an important parameter for producing material with multifunctional characteristics suitable for drug delivery and tissue engineering.
PB  - Elsevier Sci Ltd, Oxford
T2  - Composites Part B-Engineering
T1  - Improvement of mechanical properties and antibacterial activity of crosslinked electrospun chitosan/poly (ethylene oxide) nanofibers
EP  - 67
SP  - 58
VL  - 121
DO  - 10.1016/j.compositesb.2017.03.024
ER  - 

@article{
author = "Grković, Mirjana and Stojanović, Dušica and Pavlović, Vladimir B. and Rajilić-Stojanović, Mirjana and Bjelović, Miloš and Uskoković, Petar",
year = "2017",
abstract = "In this study conditions for green crosslinking with citric acid of chitosan/PEO (polyethylene oxide) nanofibers were evaluated. The thermal in situ crosslinking enabled penetration of crosslinking agent into the matrix providing an improvement of antibacterial activity, thermal stability and mechanical properties of the prepared material. With an increase of temperature above 80 degrees C antibacterial activity against Staphylococcus aureus and Escherichia coil, inversely decreased. Moreover crosslinking provided prolonged controlled drug release with outstanding increase of mechanical properties observed by nanoindentation measurements. Results of the investigation indicated crosslinking as an important parameter for producing material with multifunctional characteristics suitable for drug delivery and tissue engineering.",
publisher = "Elsevier Sci Ltd, Oxford",
journal = "Composites Part B-Engineering",
title = "Improvement of mechanical properties and antibacterial activity of crosslinked electrospun chitosan/poly (ethylene oxide) nanofibers",
pages = "67-58",
volume = "121",
doi = "10.1016/j.compositesb.2017.03.024"
}

Grković, M., Stojanović, D., Pavlović, V. B., Rajilić-Stojanović, M., Bjelović, M.,& Uskoković, P.. (2017). Improvement of mechanical properties and antibacterial activity of crosslinked electrospun chitosan/poly (ethylene oxide) nanofibers. in Composites Part B-Engineering
Elsevier Sci Ltd, Oxford., 121, 58-67.
https://doi.org/10.1016/j.compositesb.2017.03.024

Grković M, Stojanović D, Pavlović VB, Rajilić-Stojanović M, Bjelović M, Uskoković P. Improvement of mechanical properties and antibacterial activity of crosslinked electrospun chitosan/poly (ethylene oxide) nanofibers. in Composites Part B-Engineering. 2017;121:58-67.
doi:10.1016/j.compositesb.2017.03.024 .

Grković, Mirjana, Stojanović, Dušica, Pavlović, Vladimir B., Rajilić-Stojanović, Mirjana, Bjelović, Miloš, Uskoković, Petar, "Improvement of mechanical properties and antibacterial activity of crosslinked electrospun chitosan/poly (ethylene oxide) nanofibers" in Composites Part B-Engineering, 121 (2017):58-67,
https://doi.org/10.1016/j.compositesb.2017.03.024 . .

TY  - JOUR
AU  - Grković, Mirjana
AU  - Stojanović, Dušica
AU  - Kojović, Aleksandar
AU  - Strnad, Simona
AU  - Kreže, Tatjana
AU  - Aleksić, Radoslav
AU  - Uskoković, Petar
PY  - 2015
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3068
AB  - Polyethylene oxide (PEO) functionalized graphene (f-G) was prepared by ultrasonication of pristine graphene in PEO aqueous solution. The feasible sonication protocol of PEO degradation and graphene functionalization enabled fabrication of solvent cast nanocomposites. Additionally, the steps to form new bio-nanocomposite films have been described. Taking the advantage of the combination of graphene, PEO and keratin fibers from poultry feather waste, the aforementioned bio-nanocomposite films were designed with extraordinary properties allowing the films to have promising applications as eventual packaging materials and enabling bio-waste keratin to be converted into value-added materials. Compared to neat PEO, addition of only 0.3 wt% f-G provided an increase of 92% to the storage modulus. These findings are similar to the nanoindentation results, which yielded increases in the reduced modulus of the same composition by about 92%. Nanoindentation testing shows that the incorporation of 0.3 wt% f-G increased the reduced modulus and hardness of the keratin-PEO blend by about 155 and 99%, respectively.
PB  - Royal Society of Chemistry
T2  - RSC Advances
T1  - Keratin-polyethylene oxide bio-nanocomposites reinforced with ultrasonically functionalized graphene
EP  - 91287
IS  - 111
SP  - 91280
VL  - 5
DO  - 10.1039/c5ra12402f
ER  - 

@article{
author = "Grković, Mirjana and Stojanović, Dušica and Kojović, Aleksandar and Strnad, Simona and Kreže, Tatjana and Aleksić, Radoslav and Uskoković, Petar",
year = "2015",
abstract = "Polyethylene oxide (PEO) functionalized graphene (f-G) was prepared by ultrasonication of pristine graphene in PEO aqueous solution. The feasible sonication protocol of PEO degradation and graphene functionalization enabled fabrication of solvent cast nanocomposites. Additionally, the steps to form new bio-nanocomposite films have been described. Taking the advantage of the combination of graphene, PEO and keratin fibers from poultry feather waste, the aforementioned bio-nanocomposite films were designed with extraordinary properties allowing the films to have promising applications as eventual packaging materials and enabling bio-waste keratin to be converted into value-added materials. Compared to neat PEO, addition of only 0.3 wt% f-G provided an increase of 92% to the storage modulus. These findings are similar to the nanoindentation results, which yielded increases in the reduced modulus of the same composition by about 92%. Nanoindentation testing shows that the incorporation of 0.3 wt% f-G increased the reduced modulus and hardness of the keratin-PEO blend by about 155 and 99%, respectively.",
publisher = "Royal Society of Chemistry",
journal = "RSC Advances",
title = "Keratin-polyethylene oxide bio-nanocomposites reinforced with ultrasonically functionalized graphene",
pages = "91287-91280",
number = "111",
volume = "5",
doi = "10.1039/c5ra12402f"
}

Grković, M., Stojanović, D., Kojović, A., Strnad, S., Kreže, T., Aleksić, R.,& Uskoković, P.. (2015). Keratin-polyethylene oxide bio-nanocomposites reinforced with ultrasonically functionalized graphene. in RSC Advances
Royal Society of Chemistry., 5(111), 91280-91287.
https://doi.org/10.1039/c5ra12402f

Grković M, Stojanović D, Kojović A, Strnad S, Kreže T, Aleksić R, Uskoković P. Keratin-polyethylene oxide bio-nanocomposites reinforced with ultrasonically functionalized graphene. in RSC Advances. 2015;5(111):91280-91287.
doi:10.1039/c5ra12402f .

Grković, Mirjana, Stojanović, Dušica, Kojović, Aleksandar, Strnad, Simona, Kreže, Tatjana, Aleksić, Radoslav, Uskoković, Petar, "Keratin-polyethylene oxide bio-nanocomposites reinforced with ultrasonically functionalized graphene" in RSC Advances, 5, no. 111 (2015):91280-91287,
https://doi.org/10.1039/c5ra12402f . .

TY  - JOUR
AU  - Obradović, Vera
AU  - Stojanović, D.
AU  - Grković, Mirjana
AU  - Živković, Irena
AU  - Radojević, Vesna
AU  - Uskoković, Petar
AU  - Aleksić, Radoslav
PY  - 2013
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2324
AB  - In this study six samples of polyurethane/p-aramid multiaxial fabric forms (Colon fabrics) were coated with 10 wt.% poly (vinyl butyral) (PVB)/ethanol solution with the addition of multiwalled carbon nanotubes (MWCNT). The solution was impregnated on both sides of each of the fabrics. All composite samples consisted of four layers of the impregnated fabrics. The MWCNT/PVB content was 0, 0.1 and 1 wt.%. The three samples of the fabrics with different MWCNT/PVB content were coated with y-aminopropyltriethoxysilane (AMEO silane)/ethanol solution due to the surface modification. The mechanical properties of the prepared composite samples were studied by dynamic mechanical analysis (DMA). The 60% increase in storage modulus was achieved by addition of MWCNT and impregnation of aramid fabrics with AMEO silane. The pristine multiwalled carbon nanotubes (MWCNT) were introduced in order to enhance additionally the mechanical properties of the materials for ballistic protection.
PB  - Association of Metallurgical Engineers of Serbia
T2  - Metallurgical & Materials Engineering
T1  - Dynamic mechanical properties of aramid fabrics impregnated with carbon nanotube/poly (vinyl butyral)/ethanol solution
EP  - 266
IS  - 3
SP  - 259
VL  - 19
UR  - https://hdl.handle.net/21.15107/rcub_technorep_2324
ER  - 

@article{
author = "Obradović, Vera and Stojanović, D. and Grković, Mirjana and Živković, Irena and Radojević, Vesna and Uskoković, Petar and Aleksić, Radoslav",
year = "2013",
abstract = "In this study six samples of polyurethane/p-aramid multiaxial fabric forms (Colon fabrics) were coated with 10 wt.% poly (vinyl butyral) (PVB)/ethanol solution with the addition of multiwalled carbon nanotubes (MWCNT). The solution was impregnated on both sides of each of the fabrics. All composite samples consisted of four layers of the impregnated fabrics. The MWCNT/PVB content was 0, 0.1 and 1 wt.%. The three samples of the fabrics with different MWCNT/PVB content were coated with y-aminopropyltriethoxysilane (AMEO silane)/ethanol solution due to the surface modification. The mechanical properties of the prepared composite samples were studied by dynamic mechanical analysis (DMA). The 60% increase in storage modulus was achieved by addition of MWCNT and impregnation of aramid fabrics with AMEO silane. The pristine multiwalled carbon nanotubes (MWCNT) were introduced in order to enhance additionally the mechanical properties of the materials for ballistic protection.",
publisher = "Association of Metallurgical Engineers of Serbia",
journal = "Metallurgical & Materials Engineering",
title = "Dynamic mechanical properties of aramid fabrics impregnated with carbon nanotube/poly (vinyl butyral)/ethanol solution",
pages = "266-259",
number = "3",
volume = "19",
url = "https://hdl.handle.net/21.15107/rcub_technorep_2324"
}

Obradović, V., Stojanović, D., Grković, M., Živković, I., Radojević, V., Uskoković, P.,& Aleksić, R.. (2013). Dynamic mechanical properties of aramid fabrics impregnated with carbon nanotube/poly (vinyl butyral)/ethanol solution. in Metallurgical & Materials Engineering
Association of Metallurgical Engineers of Serbia., 19(3), 259-266.
https://hdl.handle.net/21.15107/rcub_technorep_2324

Obradović V, Stojanović D, Grković M, Živković I, Radojević V, Uskoković P, Aleksić R. Dynamic mechanical properties of aramid fabrics impregnated with carbon nanotube/poly (vinyl butyral)/ethanol solution. in Metallurgical & Materials Engineering. 2013;19(3):259-266.
https://hdl.handle.net/21.15107/rcub_technorep_2324 .

Obradović, Vera, Stojanović, D., Grković, Mirjana, Živković, Irena, Radojević, Vesna, Uskoković, Petar, Aleksić, Radoslav, "Dynamic mechanical properties of aramid fabrics impregnated with carbon nanotube/poly (vinyl butyral)/ethanol solution" in Metallurgical & Materials Engineering, 19, no. 3 (2013):259-266,
https://hdl.handle.net/21.15107/rcub_technorep_2324 .

TY  - JOUR
AU  - Valentini, Luca
AU  - Cardinali, Marta
AU  - Grković, Mirjana
AU  - Uskoković, Petar
AU  - Alimenti, Federico
AU  - Roselli, Luca
AU  - Kenny, Jose M.
PY  - 2013
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/2421
AB  - In this paper we report: the use of graphene oxide in aqueous solution as a gate dielectric material, its application to a MOS transistor based on organic semiconductor and the use of paper as substrate material.
PB  - Amer Scientific Publishers, Valencia
T2  - Science of Advanced Materials
T1  - Flexible Transistors Exploiting P3HT on Paper Substrate and Graphene Oxide Film as Gate Dielectric: Proof of Concept
EP  - 533
IS  - 5
SP  - 530
VL  - 5
DO  - 10.1166/sam.2013.1484
ER  - 

@article{
author = "Valentini, Luca and Cardinali, Marta and Grković, Mirjana and Uskoković, Petar and Alimenti, Federico and Roselli, Luca and Kenny, Jose M.",
year = "2013",
abstract = "In this paper we report: the use of graphene oxide in aqueous solution as a gate dielectric material, its application to a MOS transistor based on organic semiconductor and the use of paper as substrate material.",
publisher = "Amer Scientific Publishers, Valencia",
journal = "Science of Advanced Materials",
title = "Flexible Transistors Exploiting P3HT on Paper Substrate and Graphene Oxide Film as Gate Dielectric: Proof of Concept",
pages = "533-530",
number = "5",
volume = "5",
doi = "10.1166/sam.2013.1484"
}

Valentini, L., Cardinali, M., Grković, M., Uskoković, P., Alimenti, F., Roselli, L.,& Kenny, J. M.. (2013). Flexible Transistors Exploiting P3HT on Paper Substrate and Graphene Oxide Film as Gate Dielectric: Proof of Concept. in Science of Advanced Materials
Amer Scientific Publishers, Valencia., 5(5), 530-533.
https://doi.org/10.1166/sam.2013.1484

Valentini L, Cardinali M, Grković M, Uskoković P, Alimenti F, Roselli L, Kenny JM. Flexible Transistors Exploiting P3HT on Paper Substrate and Graphene Oxide Film as Gate Dielectric: Proof of Concept. in Science of Advanced Materials. 2013;5(5):530-533.
doi:10.1166/sam.2013.1484 .

Valentini, Luca, Cardinali, Marta, Grković, Mirjana, Uskoković, Petar, Alimenti, Federico, Roselli, Luca, Kenny, Jose M., "Flexible Transistors Exploiting P3HT on Paper Substrate and Graphene Oxide Film as Gate Dielectric: Proof of Concept" in Science of Advanced Materials, 5, no. 5 (2013):530-533,
https://doi.org/10.1166/sam.2013.1484 . .