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  - Sustersić, Tijana
AU  - Liverani, Liliana
AU  - Boccaccini, Aldo R.
AU  - Savić, Slobodan
AU  - Janićijević, Aco
AU  - Filipović, Nenad
PY  - 2019
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/4338
AB  - The aim of this research was to investigate if it is possible to implicitly determine the homogeneity of the obtained electrospun fibers based on jet shape during electrospinning. Experiments were performed with 10 wt% PVA solution, and four variations in process parameters were investigated in order to examine their effect on fiber structure. Data obtained during experiments were used as input for computational simulation. The simulation results, both using commercial ANSYS and in-house software PAK, show good agreement with experiments in terms of outcome-no fiber differences in experiments were present when different voltage pairs were used, and similar jet shapes were obtained during simulations. Shapes of the electric field potential for all the used voltage pairs were very similar, due to the uniformity of the field, which is in agreement with the experiment, as no differences in fiber structure are observed in these cases. This confirms the hypothesis that based on jet shape during electrospinning, it is possible to implicitly determine the homogeneity of the obtained electrospun fibers. Differences that may occur between experiments and simulation can be a result of simplifications in simulations, influence of uniform and non-uniform electric field etc. This kind of two-phase simulation could be useful in reducing the trial-and-error approach and maintenance costs in electrospinning experiments.
PB  - IOP Publishing Ltd, Bristol
T2  - Materials Research Express
T1  - Numerical simulation of electrospinning process in commercial and in-house software PAK
IS  - 2
VL  - 6
DO  - 10.1088/2053-1591/aaeb08
ER  - 

@article{
author = "Sustersić, Tijana and Liverani, Liliana and Boccaccini, Aldo R. and Savić, Slobodan and Janićijević, Aco and Filipović, Nenad",
year = "2019",
abstract = "The aim of this research was to investigate if it is possible to implicitly determine the homogeneity of the obtained electrospun fibers based on jet shape during electrospinning. Experiments were performed with 10 wt% PVA solution, and four variations in process parameters were investigated in order to examine their effect on fiber structure. Data obtained during experiments were used as input for computational simulation. The simulation results, both using commercial ANSYS and in-house software PAK, show good agreement with experiments in terms of outcome-no fiber differences in experiments were present when different voltage pairs were used, and similar jet shapes were obtained during simulations. Shapes of the electric field potential for all the used voltage pairs were very similar, due to the uniformity of the field, which is in agreement with the experiment, as no differences in fiber structure are observed in these cases. This confirms the hypothesis that based on jet shape during electrospinning, it is possible to implicitly determine the homogeneity of the obtained electrospun fibers. Differences that may occur between experiments and simulation can be a result of simplifications in simulations, influence of uniform and non-uniform electric field etc. This kind of two-phase simulation could be useful in reducing the trial-and-error approach and maintenance costs in electrospinning experiments.",
publisher = "IOP Publishing Ltd, Bristol",
journal = "Materials Research Express",
title = "Numerical simulation of electrospinning process in commercial and in-house software PAK",
number = "2",
volume = "6",
doi = "10.1088/2053-1591/aaeb08"
}

Sustersić, T., Liverani, L., Boccaccini, A. R., Savić, S., Janićijević, A.,& Filipović, N.. (2019). Numerical simulation of electrospinning process in commercial and in-house software PAK. in Materials Research Express
IOP Publishing Ltd, Bristol., 6(2).
https://doi.org/10.1088/2053-1591/aaeb08

Sustersić T, Liverani L, Boccaccini AR, Savić S, Janićijević A, Filipović N. Numerical simulation of electrospinning process in commercial and in-house software PAK. in Materials Research Express. 2019;6(2).
doi:10.1088/2053-1591/aaeb08 .

Sustersić, Tijana, Liverani, Liliana, Boccaccini, Aldo R., Savić, Slobodan, Janićijević, Aco, Filipović, Nenad, "Numerical simulation of electrospinning process in commercial and in-house software PAK" in Materials Research Express, 6, no. 2 (2019),
https://doi.org/10.1088/2053-1591/aaeb08 . .

TY  - JOUR
AU  - Milosević, Miljan
AU  - Stojanović, Dušica
AU  - Simić, Vladimir
AU  - Milicević, Bogdan
AU  - Radisavljević, Anđela
AU  - Uskoković, Petar
AU  - Kojić, Miloš
PY  - 2018
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3912
AB  - Due to the relative ease of producing nanofibers with a core-shell structure, emulsion electrospinning has been investigated intensively in making nanofibrous drug delivery systems for controlled and sustained release. Predictions of drug release rates from the poly (D, L-lactic-co-glycolic acid) (PLGA) produced via emulsion electrospinning can be a very difficult task due to the complexity of the system. A computational finite element methodology was used to calculate the diffusion mass transport of Rhodamine B (fluorescent drug model). Degradation effects and hydrophobicity (partitioning phenomenon) at the fiber/surrounding interface were included in the models. The results are validated by experiments where electrospun PLGA nanofiber mats with different contents were used. A new approach to three-dimensional (3D) modeling of nanofibers is presented in this work. The authors have introduced two original models for diffusive drug release from nanofibers to the 3D surrounding medium discretized by continuum 3D finite elements: (1) A model with simple radial one-dimensional (1D) finite elements, and (2) a model consisting of composite smeared finite elements (CSFEs). Numerical solutions, compared to experiments, demonstrate that both computational models provide accurate predictions of the diffusion process and can therefore serve as efficient tools for describing transport inside a polymer fiber network and drug release to the surrounding porous medium.
PB  - MDPI, Basel
T2  - Materials
T1  - A Computational Model for Drug Release from PLGA Implant
IS  - 12
VL  - 11
DO  - 10.3390/ma11122416
ER  - 

@article{
author = "Milosević, Miljan and Stojanović, Dušica and Simić, Vladimir and Milicević, Bogdan and Radisavljević, Anđela and Uskoković, Petar and Kojić, Miloš",
year = "2018",
abstract = "Due to the relative ease of producing nanofibers with a core-shell structure, emulsion electrospinning has been investigated intensively in making nanofibrous drug delivery systems for controlled and sustained release. Predictions of drug release rates from the poly (D, L-lactic-co-glycolic acid) (PLGA) produced via emulsion electrospinning can be a very difficult task due to the complexity of the system. A computational finite element methodology was used to calculate the diffusion mass transport of Rhodamine B (fluorescent drug model). Degradation effects and hydrophobicity (partitioning phenomenon) at the fiber/surrounding interface were included in the models. The results are validated by experiments where electrospun PLGA nanofiber mats with different contents were used. A new approach to three-dimensional (3D) modeling of nanofibers is presented in this work. The authors have introduced two original models for diffusive drug release from nanofibers to the 3D surrounding medium discretized by continuum 3D finite elements: (1) A model with simple radial one-dimensional (1D) finite elements, and (2) a model consisting of composite smeared finite elements (CSFEs). Numerical solutions, compared to experiments, demonstrate that both computational models provide accurate predictions of the diffusion process and can therefore serve as efficient tools for describing transport inside a polymer fiber network and drug release to the surrounding porous medium.",
publisher = "MDPI, Basel",
journal = "Materials",
title = "A Computational Model for Drug Release from PLGA Implant",
number = "12",
volume = "11",
doi = "10.3390/ma11122416"
}

Milosević, M., Stojanović, D., Simić, V., Milicević, B., Radisavljević, A., Uskoković, P.,& Kojić, M.. (2018). A Computational Model for Drug Release from PLGA Implant. in Materials
MDPI, Basel., 11(12).
https://doi.org/10.3390/ma11122416

Milosević M, Stojanović D, Simić V, Milicević B, Radisavljević A, Uskoković P, Kojić M. A Computational Model for Drug Release from PLGA Implant. in Materials. 2018;11(12).
doi:10.3390/ma11122416 .

Milosević, Miljan, Stojanović, Dušica, Simić, Vladimir, Milicević, Bogdan, Radisavljević, Anđela, Uskoković, Petar, Kojić, Miloš, "A Computational Model for Drug Release from PLGA Implant" in Materials, 11, no. 12 (2018),
https://doi.org/10.3390/ma11122416 . .

TY  - JOUR
AU  - Kojić, M.
AU  - Milosević, M.
AU  - Simić, Vladimir
AU  - Stojanović, Dušica
AU  - Uskoković, Petar
PY  - 2017
UR  - http://TechnoRep.tmf.bg.ac.rs/handle/123456789/3644
AB  - The aim of this study was to investigate the release performance of an electrospun composite drug loaded nanofiber mat. Electrospun nanofiber mats are promising as drug carriers which offer site-specific delivery of drugs to a target in the human body and may be used for cancer therapy. The authors have formulated a simple radial 1D finite element, which is used to model diffusion within fibers releasing a drug to the surrounding medium discretized by continuum 3D finite elements. The numerical model includes degradation effects and hydrophobicity at the fibers/surroundings interface. For the purpose of experimental investigation, a poly(D, L-lacticco-glycolic acid) (PLGA) implant has been created at the Faculty of Technology and Metallurgy, University of Belgrade. The radial 1D element provides accurate predictions of the diffusion process and serves as an efficient tool for describing transport inside the polymer fiber and surrounding porous medium; which is illustrated through numerical examples.
PB  - Univerzitet u Kragujevcu - Fakultet inženjerskih nauka, Kragujevac
T2  - Journal of the Serbian Society for Computational Mechanics
T1  - A radial 1D Finite Element for Drug Release from Drug Loaded Nanofibers
EP  - 93
IS  - 1
SP  - 82
VL  - 11
DO  - 10.24874/jsscm.2017.11.01.08
ER  - 

@article{
author = "Kojić, M. and Milosević, M. and Simić, Vladimir and Stojanović, Dušica and Uskoković, Petar",
year = "2017",
abstract = "The aim of this study was to investigate the release performance of an electrospun composite drug loaded nanofiber mat. Electrospun nanofiber mats are promising as drug carriers which offer site-specific delivery of drugs to a target in the human body and may be used for cancer therapy. The authors have formulated a simple radial 1D finite element, which is used to model diffusion within fibers releasing a drug to the surrounding medium discretized by continuum 3D finite elements. The numerical model includes degradation effects and hydrophobicity at the fibers/surroundings interface. For the purpose of experimental investigation, a poly(D, L-lacticco-glycolic acid) (PLGA) implant has been created at the Faculty of Technology and Metallurgy, University of Belgrade. The radial 1D element provides accurate predictions of the diffusion process and serves as an efficient tool for describing transport inside the polymer fiber and surrounding porous medium; which is illustrated through numerical examples.",
publisher = "Univerzitet u Kragujevcu - Fakultet inženjerskih nauka, Kragujevac",
journal = "Journal of the Serbian Society for Computational Mechanics",
title = "A radial 1D Finite Element for Drug Release from Drug Loaded Nanofibers",
pages = "93-82",
number = "1",
volume = "11",
doi = "10.24874/jsscm.2017.11.01.08"
}

Kojić, M., Milosević, M., Simić, V., Stojanović, D.,& Uskoković, P.. (2017). A radial 1D Finite Element for Drug Release from Drug Loaded Nanofibers. in Journal of the Serbian Society for Computational Mechanics
Univerzitet u Kragujevcu - Fakultet inženjerskih nauka, Kragujevac., 11(1), 82-93.
https://doi.org/10.24874/jsscm.2017.11.01.08

Kojić M, Milosević M, Simić V, Stojanović D, Uskoković P. A radial 1D Finite Element for Drug Release from Drug Loaded Nanofibers. in Journal of the Serbian Society for Computational Mechanics. 2017;11(1):82-93.
doi:10.24874/jsscm.2017.11.01.08 .

Kojić, M., Milosević, M., Simić, Vladimir, Stojanović, Dušica, Uskoković, Petar, "A radial 1D Finite Element for Drug Release from Drug Loaded Nanofibers" in Journal of the Serbian Society for Computational Mechanics, 11, no. 1 (2017):82-93,
https://doi.org/10.24874/jsscm.2017.11.01.08 . .