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Filipič, Metka

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  • Filipič, Metka (18)

Author's Bibliography

Supplementary information for the article: Filipović, N., Veselinović, L., Ražić, S., Jeremić, S., Filipič, M., Žegura, B., Tomić, S., Čolić, M., Stevanović, M., 2019. Poly (ε-caprolactone) microspheres for prolonged release of selenium nanoparticles. Materials Science and Engineering C 96, 776–789. https://doi.org/10.1016/j.msec.2018.11.073

Filipović, Nenad; Veselinović, Ljiljana; Ražić, Slavica; Jeremić, Sanja; Filipič, Metka; Žegura, Bojana; Tomić, Sergej; Čolić, Miodrag; Stevanović, Magdalena

(2019)

@misc{
author = "Filipović, Nenad and Veselinović, Ljiljana and Ražić, Slavica and Jeremić, Sanja and Filipič, Metka and Žegura, Bojana and Tomić, Sergej and Čolić, Miodrag and Stevanović, Magdalena",
year = "2019",
url = "http://dais.sanu.ac.rs/123456789/5972",
journal = "Materials Science and Engineering C",
title = "Supplementary information for the article: Filipović, N., Veselinović, L., Ražić, S., Jeremić, S., Filipič, M., Žegura, B., Tomić, S., Čolić, M., Stevanović, M., 2019. Poly (ε-caprolactone) microspheres for prolonged release of selenium nanoparticles. Materials Science and Engineering C 96, 776–789. https://doi.org/10.1016/j.msec.2018.11.073"
}

Poly (ε-caprolactone) microspheres for prolonged release of selenium nanoparticles

Filipović, Nenad; Veselinović, Ljiljana; Ražić, Slavica; Jeremić, Sanja; Filipič, Metka; Žegura, Bojana; Tomić, Sergej; Čolić, Miodrag; Stevanović, Magdalena

(Elsevier, 2019)

TY  - JOUR
AU  - Filipović, Nenad
AU  - Veselinović, Ljiljana
AU  - Ražić, Slavica
AU  - Jeremić, Sanja
AU  - Filipič, Metka
AU  - Žegura, Bojana
AU  - Tomić, Sergej
AU  - Čolić, Miodrag
AU  - Stevanović, Magdalena
PY  - 2019
UR  - http://dais.sanu.ac.rs/123456789/4600
AB  - Poly (ε-caprolactone) (PCL) microspheres as a carrier for sustained release of antibacterial agent, selenium nanoparticles (SeNPs), were developed. The obtained PCL/SeNPs microspheres were in the range 1–4 μm with the encapsulation efficiency of about 90%. The degradation process and release behavior of SeNPs from PCL microspheres were investigated in five different degradation media: phosphate buffer solution (PBS), a solution of lipase isolated from the porcine pancreas in PBS, 0.1 M hydrochloric acid (HCl), Pseudomonas aeruginosa PAO1 cell-free extract in PBS and implant fluid (exudate) from the subcutaneously implanted sterile polyvinyl sponges which induce a foreign-body inflammatory reaction. The samples were thoroughly characterized by SEM, TEM, FTIR, XRD, PSA, DSC, confocal microscopy, and ICP-OES techniques. Under physiological conditions at neutral pH, a very slow release of SeNPs occurred (3 and 8% in the case of PBS or PBS + lipase, respectively and after 660 days), while in the acidic environment their presence was not detected. On the other hand, the release in the medium with bacterial extract was much more pronounced, even after 24 h (13%). After 7 days, the concentration of SeNPs reached a maximum of around 30%. Also, 37% of SeNPs have been released after 11 days of incubation of PCL/SeNPs in the implant exudate. These results suggest that the release of SeNPs from PCL was triggered by Pseudomonas aeruginosa PAO1 bacterium as well as by foreign body inflammatory reaction to implant. Furthermore, PCL/SeNPs microspheres were investigated in terms of their biocompatibility. For this purpose, cytotoxicity, the formation of reactive oxygen species (ROS), and genotoxicity were evaluated on HepG2 cell line. The interaction of PCL/SeNPs with phagocytic cell line (Raw 264.7 macrophages) was monitored as well. It was found that the microspheres in investigated concentration range had no acute cytotoxic effects. Finally, SeNPs, as well as PCL/SeNPs, showed a considerable antibacterial activity against Gram-positive bacteria: Staphylococcus aureus (ATCC 25923) and Staphylococcus epidermidis (ATCC 1228). These results suggest that PCL/SeNPs-based system could be an attractive platform for a prolonged prevention of infections accompanying implants. © 2018 Elsevier B.V.
PB  - Elsevier
T2  - Materials Science and Engineering C
T1  - Poly (ε-caprolactone) microspheres for prolonged release of selenium nanoparticles
SP  - 776
EP  - 789
VL  - 96
DO  - 10.1016/j.msec.2018.11.073
ER  - 
@article{
author = "Filipović, Nenad and Veselinović, Ljiljana and Ražić, Slavica and Jeremić, Sanja and Filipič, Metka and Žegura, Bojana and Tomić, Sergej and Čolić, Miodrag and Stevanović, Magdalena",
year = "2019",
url = "http://dais.sanu.ac.rs/123456789/4600",
abstract = "Poly (ε-caprolactone) (PCL) microspheres as a carrier for sustained release of antibacterial agent, selenium nanoparticles (SeNPs), were developed. The obtained PCL/SeNPs microspheres were in the range 1–4 μm with the encapsulation efficiency of about 90%. The degradation process and release behavior of SeNPs from PCL microspheres were investigated in five different degradation media: phosphate buffer solution (PBS), a solution of lipase isolated from the porcine pancreas in PBS, 0.1 M hydrochloric acid (HCl), Pseudomonas aeruginosa PAO1 cell-free extract in PBS and implant fluid (exudate) from the subcutaneously implanted sterile polyvinyl sponges which induce a foreign-body inflammatory reaction. The samples were thoroughly characterized by SEM, TEM, FTIR, XRD, PSA, DSC, confocal microscopy, and ICP-OES techniques. Under physiological conditions at neutral pH, a very slow release of SeNPs occurred (3 and 8% in the case of PBS or PBS + lipase, respectively and after 660 days), while in the acidic environment their presence was not detected. On the other hand, the release in the medium with bacterial extract was much more pronounced, even after 24 h (13%). After 7 days, the concentration of SeNPs reached a maximum of around 30%. Also, 37% of SeNPs have been released after 11 days of incubation of PCL/SeNPs in the implant exudate. These results suggest that the release of SeNPs from PCL was triggered by Pseudomonas aeruginosa PAO1 bacterium as well as by foreign body inflammatory reaction to implant. Furthermore, PCL/SeNPs microspheres were investigated in terms of their biocompatibility. For this purpose, cytotoxicity, the formation of reactive oxygen species (ROS), and genotoxicity were evaluated on HepG2 cell line. The interaction of PCL/SeNPs with phagocytic cell line (Raw 264.7 macrophages) was monitored as well. It was found that the microspheres in investigated concentration range had no acute cytotoxic effects. Finally, SeNPs, as well as PCL/SeNPs, showed a considerable antibacterial activity against Gram-positive bacteria: Staphylococcus aureus (ATCC 25923) and Staphylococcus epidermidis (ATCC 1228). These results suggest that PCL/SeNPs-based system could be an attractive platform for a prolonged prevention of infections accompanying implants. © 2018 Elsevier B.V.",
publisher = "Elsevier",
journal = "Materials Science and Engineering C",
title = "Poly (ε-caprolactone) microspheres for prolonged release of selenium nanoparticles",
pages = "776-789",
volume = "96",
doi = "10.1016/j.msec.2018.11.073"
}
1
4
6
7

Poly (ε-caprolactone) microspheres for prolonged release of selenium nanoparticles

Filipović, Nenad; Veselinović, Ljiljana; Ražić, Slavica; Jeremić, Sanja; Filipič, Metka; Žegura, Bojana; Tomić, Sergej; Čolić, Miodrag; Stevanović, Magdalena

(Elsevier, 2019)

TY  - JOUR
AU  - Filipović, Nenad
AU  - Veselinović, Ljiljana
AU  - Ražić, Slavica
AU  - Jeremić, Sanja
AU  - Filipič, Metka
AU  - Žegura, Bojana
AU  - Tomić, Sergej
AU  - Čolić, Miodrag
AU  - Stevanović, Magdalena
PY  - 2019
UR  - http://dais.sanu.ac.rs/123456789/4590
AB  - Poly (ε-caprolactone) (PCL) microspheres as a carrier for sustained release of antibacterial agent, selenium nanoparticles (SeNPs), were developed. The obtained PCL/SeNPs microspheres were in the range 1–4 μm with the encapsulation efficiency of about 90%. The degradation process and release behavior of SeNPs from PCL microspheres were investigated in five different degradation media: phosphate buffer solution (PBS), a solution of lipase isolated from the porcine pancreas in PBS, 0.1 M hydrochloric acid (HCl), Pseudomonas aeruginosa PAO1 cell-free extract in PBS and implant fluid (exudate) from the subcutaneously implanted sterile polyvinyl sponges which induce a foreign-body inflammatory reaction. The samples were thoroughly characterized by SEM, TEM, FTIR, XRD, PSA, DSC, confocal microscopy, and ICP-OES techniques. Under physiological conditions at neutral pH, a very slow release of SeNPs occurred (3 and 8% in the case of PBS or PBS + lipase, respectively and after 660 days), while in the acidic environment their presence was not detected. On the other hand, the release in the medium with bacterial extract was much more pronounced, even after 24 h (13%). After 7 days, the concentration of SeNPs reached a maximum of around 30%. Also, 37% of SeNPs have been released after 11 days of incubation of PCL/SeNPs in the implant exudate. These results suggest that the release of SeNPs from PCL was triggered by Pseudomonas aeruginosa PAO1 bacterium as well as by foreign body inflammatory reaction to implant. Furthermore, PCL/SeNPs microspheres were investigated in terms of their biocompatibility. For this purpose, cytotoxicity, the formation of reactive oxygen species (ROS), and genotoxicity were evaluated on HepG2 cell line. The interaction of PCL/SeNPs with phagocytic cell line (Raw 264.7 macrophages) was monitored as well. It was found that the microspheres in investigated concentration range had no acute cytotoxic effects. Finally, SeNPs, as well as PCL/SeNPs, showed a considerable antibacterial activity against Gram-positive bacteria: Staphylococcus aureus (ATCC 25923) and Staphylococcus epidermidis (ATCC 1228). These results suggest that PCL/SeNPs-based system could be an attractive platform for a prolonged prevention of infections accompanying implants. © 2018 Elsevier B.V.
PB  - Elsevier
T2  - Materials Science and Engineering C
T1  - Poly (ε-caprolactone) microspheres for prolonged release of selenium nanoparticles
SP  - 776
EP  - 789
VL  - 96
DO  - 10.1016/j.msec.2018.11.073
ER  - 
@article{
author = "Filipović, Nenad and Veselinović, Ljiljana and Ražić, Slavica and Jeremić, Sanja and Filipič, Metka and Žegura, Bojana and Tomić, Sergej and Čolić, Miodrag and Stevanović, Magdalena",
year = "2019",
url = "http://dais.sanu.ac.rs/123456789/4590",
abstract = "Poly (ε-caprolactone) (PCL) microspheres as a carrier for sustained release of antibacterial agent, selenium nanoparticles (SeNPs), were developed. The obtained PCL/SeNPs microspheres were in the range 1–4 μm with the encapsulation efficiency of about 90%. The degradation process and release behavior of SeNPs from PCL microspheres were investigated in five different degradation media: phosphate buffer solution (PBS), a solution of lipase isolated from the porcine pancreas in PBS, 0.1 M hydrochloric acid (HCl), Pseudomonas aeruginosa PAO1 cell-free extract in PBS and implant fluid (exudate) from the subcutaneously implanted sterile polyvinyl sponges which induce a foreign-body inflammatory reaction. The samples were thoroughly characterized by SEM, TEM, FTIR, XRD, PSA, DSC, confocal microscopy, and ICP-OES techniques. Under physiological conditions at neutral pH, a very slow release of SeNPs occurred (3 and 8% in the case of PBS or PBS + lipase, respectively and after 660 days), while in the acidic environment their presence was not detected. On the other hand, the release in the medium with bacterial extract was much more pronounced, even after 24 h (13%). After 7 days, the concentration of SeNPs reached a maximum of around 30%. Also, 37% of SeNPs have been released after 11 days of incubation of PCL/SeNPs in the implant exudate. These results suggest that the release of SeNPs from PCL was triggered by Pseudomonas aeruginosa PAO1 bacterium as well as by foreign body inflammatory reaction to implant. Furthermore, PCL/SeNPs microspheres were investigated in terms of their biocompatibility. For this purpose, cytotoxicity, the formation of reactive oxygen species (ROS), and genotoxicity were evaluated on HepG2 cell line. The interaction of PCL/SeNPs with phagocytic cell line (Raw 264.7 macrophages) was monitored as well. It was found that the microspheres in investigated concentration range had no acute cytotoxic effects. Finally, SeNPs, as well as PCL/SeNPs, showed a considerable antibacterial activity against Gram-positive bacteria: Staphylococcus aureus (ATCC 25923) and Staphylococcus epidermidis (ATCC 1228). These results suggest that PCL/SeNPs-based system could be an attractive platform for a prolonged prevention of infections accompanying implants. © 2018 Elsevier B.V.",
publisher = "Elsevier",
journal = "Materials Science and Engineering C",
title = "Poly (ε-caprolactone) microspheres for prolonged release of selenium nanoparticles",
pages = "776-789",
volume = "96",
doi = "10.1016/j.msec.2018.11.073"
}
1
4
6
7

Synthesis, characterization and toxicity studies of gelatin modified zinc oxide nanoparticles

Janićijević, Željko; Stanković, Ana; Žegura, Bojana; Veljović, Đorđe; Filipič, Metka; Stevanović, Magdalena

(Belgrade : Institute of Technical Sciences of SASA, 2019)

TY  - CONF
AU  - Janićijević, Željko
AU  - Stanković, Ana
AU  - Žegura, Bojana
AU  - Veljović, Đorđe
AU  - Filipič, Metka
AU  - Stevanović, Magdalena
PY  - 2019
UR  - http://dais.sanu.ac.rs/123456789/6968
AB  - Nanostructured zinc oxides are promising materials for numerous biomedical applications where they can serve as therapeutic agents or tools for sensing and imaging. Despite their favorable properties, wider use of zinc oxide nanoparticles in biomedicine is limited by toxicity issues. Therefore, new synthesis approaches should be devised to obtain zinc oxide nanoparticles which are safe-by-design. We present an innovative low-cost wet precipitation synthesis of gelatin modified zinc oxide nanoparticles at the gel/liquid interface. The diffusion of ammonia through the gelatin hydrogels of different porosities induces precipitation of the product in contact with the surface of the aqueous solution of zinc ions. After thermal treatment of the precipitate, adsorbed organic residues of decomposed gelatin act as modifiers of zinc oxide nanoparticles. We characterized the physicochemical properties of obtained gelatin modified zinc oxide nanoparticles by XRD, FTIR, DTA/TG, and SEM. The synthesized nanoparticles show hexagonal wurtzite structure and form flakelike aggregates. FTIR and DTA/TG analyses indicate that the thermal decomposition of adsorbed gelatin depends on the gelatin content of the hydrogel used in the synthesis. We also examined the viability of HepG2 cells, generation of intracellular reactive oxygen species, and genotoxicity using the MTS, DCFH-DA, and alkaline comet assay, respectively. Fabricated gelatin modified zinc oxide nanoparticles show very low toxicity potential at doses relevant for human exposure.
PB  - Belgrade : Institute of Technical Sciences of SASA
C3  - Program and the Book of abstracts / Eighteenth Young Researchers' Conference Materials Sciences and Engineering, December 4-6, 2019, Belgrade, Serbia
T1  - Synthesis, characterization and toxicity studies of gelatin modified zinc oxide nanoparticles
SP  - 3
EP  - 3
ER  - 
@conference{
author = "Janićijević, Željko and Stanković, Ana and Žegura, Bojana and Veljović, Đorđe and Filipič, Metka and Stevanović, Magdalena",
year = "2019",
url = "http://dais.sanu.ac.rs/123456789/6968",
abstract = "Nanostructured zinc oxides are promising materials for numerous biomedical applications where they can serve as therapeutic agents or tools for sensing and imaging. Despite their favorable properties, wider use of zinc oxide nanoparticles in biomedicine is limited by toxicity issues. Therefore, new synthesis approaches should be devised to obtain zinc oxide nanoparticles which are safe-by-design. We present an innovative low-cost wet precipitation synthesis of gelatin modified zinc oxide nanoparticles at the gel/liquid interface. The diffusion of ammonia through the gelatin hydrogels of different porosities induces precipitation of the product in contact with the surface of the aqueous solution of zinc ions. After thermal treatment of the precipitate, adsorbed organic residues of decomposed gelatin act as modifiers of zinc oxide nanoparticles. We characterized the physicochemical properties of obtained gelatin modified zinc oxide nanoparticles by XRD, FTIR, DTA/TG, and SEM. The synthesized nanoparticles show hexagonal wurtzite structure and form flakelike aggregates. FTIR and DTA/TG analyses indicate that the thermal decomposition of adsorbed gelatin depends on the gelatin content of the hydrogel used in the synthesis. We also examined the viability of HepG2 cells, generation of intracellular reactive oxygen species, and genotoxicity using the MTS, DCFH-DA, and alkaline comet assay, respectively. Fabricated gelatin modified zinc oxide nanoparticles show very low toxicity potential at doses relevant for human exposure.",
publisher = "Belgrade : Institute of Technical Sciences of SASA",
journal = "Program and the Book of abstracts / Eighteenth Young Researchers' Conference Materials Sciences and Engineering, December 4-6, 2019, Belgrade, Serbia",
title = "Synthesis, characterization and toxicity studies of gelatin modified zinc oxide nanoparticles",
pages = "3-3"
}

Selenium nanoparticles as a potential candidate in cancer treatment

Filipović, Nenad; Ninić, Jana; Filipič, Metka; Filipović, Miloš; Stevanović, Magdalena

(Rovinj : International Association of Physical Chemists, 2015)

TY  - CONF
AU  - Filipović, Nenad
AU  - Ninić, Jana
AU  - Filipič, Metka
AU  - Filipović, Miloš
AU  - Stevanović, Magdalena
PY  - 2015
UR  - http://dais.sanu.ac.rs/123456789/858
AB  - The broad spectrum of selenium applications in pharmacy and medicine has been known for a while and strongly depends on its chemical form, size and shape. However, the use of Se often requires consumption over the long period, so the toxicity of Se is always a crucial concern. Majority of available pharmaceutical products contain organic forms of selenium or its salts, but recently, when it comes to cancer treatment, elemental selenium nanoparticles (SeNPs) have emerged as a novel selenium source with the advantage of reduced risk of selenium toxicity, but with same bioavailability and efficacy in increasing the activities of selenoenzimes. 
In this work we are presenting the fast, reproducible method for producing stable colloidal suspension of amorphous SeNPs (<80 nm). These SeNPS were successful incorporated within PCL microspheres by combining the high speed homogenization and the precipitation in a solvent/non-solvent system. The obtained PCL/SeNPs were characterized by Fourier transform infrared spectroscopy (FTIR), electron microscopy (SEM and TEM), X-ray diffraction (XRD) and thermal analysis methods (TGA-DTA). The cytotoxicity and the formation of intracellular reactive oxygen species of SeNPs as well as of PCL/SeNPs were investigated employing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and using a fluorescent probe (DCFDA test) respectively. Both systems have shown good biocompatibility. The anticancer activity of SeNPs was examined on the HeLa cell line and it was demonstrated that SeNPs exhibits strong, a dose dependent, anticancer activity by preventing further HeLa cells growth and division. Bearing in mind that PCL is well known biodegradable polymer with low degradation rate, it is our opinion that PCL/SeNPs possess a great potential for cancer treatment.
PB  - Rovinj : International Association of Physical Chemists
C3  - Joint Event 4th World Conference on Physico-Chemical Methods in Drug Discovery and Development (PCMDDD-4) and 1st World Conference on ADMET and DMPK
T1  - Selenium nanoparticles as a potential candidate in cancer treatment
ER  - 
@conference{
author = "Filipović, Nenad and Ninić, Jana and Filipič, Metka and Filipović, Miloš and Stevanović, Magdalena",
year = "2015",
url = "http://dais.sanu.ac.rs/123456789/858",
abstract = "The broad spectrum of selenium applications in pharmacy and medicine has been known for a while and strongly depends on its chemical form, size and shape. However, the use of Se often requires consumption over the long period, so the toxicity of Se is always a crucial concern. Majority of available pharmaceutical products contain organic forms of selenium or its salts, but recently, when it comes to cancer treatment, elemental selenium nanoparticles (SeNPs) have emerged as a novel selenium source with the advantage of reduced risk of selenium toxicity, but with same bioavailability and efficacy in increasing the activities of selenoenzimes. 
In this work we are presenting the fast, reproducible method for producing stable colloidal suspension of amorphous SeNPs (<80 nm). These SeNPS were successful incorporated within PCL microspheres by combining the high speed homogenization and the precipitation in a solvent/non-solvent system. The obtained PCL/SeNPs were characterized by Fourier transform infrared spectroscopy (FTIR), electron microscopy (SEM and TEM), X-ray diffraction (XRD) and thermal analysis methods (TGA-DTA). The cytotoxicity and the formation of intracellular reactive oxygen species of SeNPs as well as of PCL/SeNPs were investigated employing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and using a fluorescent probe (DCFDA test) respectively. Both systems have shown good biocompatibility. The anticancer activity of SeNPs was examined on the HeLa cell line and it was demonstrated that SeNPs exhibits strong, a dose dependent, anticancer activity by preventing further HeLa cells growth and division. Bearing in mind that PCL is well known biodegradable polymer with low degradation rate, it is our opinion that PCL/SeNPs possess a great potential for cancer treatment.",
publisher = "Rovinj : International Association of Physical Chemists",
journal = "Joint Event 4th World Conference on Physico-Chemical Methods in Drug Discovery and Development (PCMDDD-4) and 1st World Conference on ADMET and DMPK",
title = "Selenium nanoparticles as a potential candidate in cancer treatment"
}

Multifunctional PLGA particles containing poly(l-glutamic acid)-capped silver nanoparticles and ascorbic acid with simultaneous antioxidative and prolonged antimicrobial activity

Stevanović, Magdalena; Bračko, Ines; Milenković, Marina; Filipović, Nenad; Nunić, Jana; Filipič, Metka; Uskoković, Dragan

(Elsevier, 2014)

TY  - JOUR
AU  - Stevanović, Magdalena
AU  - Bračko, Ines
AU  - Milenković, Marina
AU  - Filipović, Nenad
AU  - Nunić, Jana
AU  - Filipič, Metka
AU  - Uskoković, Dragan
PY  - 2014
UR  - http://dais.sanu.ac.rs/123456789/574
AB  - A water-soluble antioxidant (ascorbic acid, vitamin C) was encapsulated together with poly(l-glutamic acid)-capped silver nanoparticles (AgNpPGA) within a poly(lactide-co-glycolide) (PLGA) polymeric matrix and their synergistic effects were studied. The PLGA/AgNpPGA/ascorbic acid particles synthesized by a physicochemical method with solvent/non-solvent systems are spherical, have a mean diameter of 775 nm and a narrow size distribution with a polydispersity index of 0.158. The encapsulation efficiency of AgNpPGA/ascorbic acid within PLGA was determined to be >90%. The entire amount of encapsulated ascorbic acid was released in 68 days, and the entire amount of AgNpPGAs was released in 87 days of degradation. The influence of PLGA/AgNpPGA/ascorbic acid on cell viability, generation of reactive oxygen species (ROS) in HepG2 cells, as well as antimicrobial activity against seven different pathogens was investigated. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay indicated good biocompatibility of these PLGA/AgNpPGA/ascorbic acid particles. We measured the kinetics of ROS formation in HepG2 cells by a DCFH-DA assay, and found that PLGA/AgNpPGA/ascorbic acid caused a significant decrease in DCF fluorescence intensity, which was 2-fold lower than that in control cells after a 5 h exposure. This indicates that the PLGA/AgNpPGA/ascorbic acid microspheres either act as scavengers of intracellular ROS and/or reduce their formation. Also, the results of antimicrobial activity of PLGA/AgNpPGA/ascorbic acid obtained by the broth microdilution method showed superior and extended activity of these particles. The samples were characterized using Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, zeta potential and particle size analysis. This paper presents a new approach to the treatment of infection that at the same time offers a very pronounced antioxidant effect.
PB  - Elsevier
T2  - Acta Biomaterialia
T1  - Multifunctional PLGA particles containing poly(l-glutamic acid)-capped silver nanoparticles and ascorbic acid with simultaneous antioxidative and prolonged antimicrobial activity
SP  - 151
EP  - 162
VL  - 10
IS  - 1
DO  - 10.1016/j.actbio.2013.08.030
ER  - 
@article{
author = "Stevanović, Magdalena and Bračko, Ines and Milenković, Marina and Filipović, Nenad and Nunić, Jana and Filipič, Metka and Uskoković, Dragan",
year = "2014",
url = "http://dais.sanu.ac.rs/123456789/574",
abstract = "A water-soluble antioxidant (ascorbic acid, vitamin C) was encapsulated together with poly(l-glutamic acid)-capped silver nanoparticles (AgNpPGA) within a poly(lactide-co-glycolide) (PLGA) polymeric matrix and their synergistic effects were studied. The PLGA/AgNpPGA/ascorbic acid particles synthesized by a physicochemical method with solvent/non-solvent systems are spherical, have a mean diameter of 775 nm and a narrow size distribution with a polydispersity index of 0.158. The encapsulation efficiency of AgNpPGA/ascorbic acid within PLGA was determined to be >90%. The entire amount of encapsulated ascorbic acid was released in 68 days, and the entire amount of AgNpPGAs was released in 87 days of degradation. The influence of PLGA/AgNpPGA/ascorbic acid on cell viability, generation of reactive oxygen species (ROS) in HepG2 cells, as well as antimicrobial activity against seven different pathogens was investigated. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay indicated good biocompatibility of these PLGA/AgNpPGA/ascorbic acid particles. We measured the kinetics of ROS formation in HepG2 cells by a DCFH-DA assay, and found that PLGA/AgNpPGA/ascorbic acid caused a significant decrease in DCF fluorescence intensity, which was 2-fold lower than that in control cells after a 5 h exposure. This indicates that the PLGA/AgNpPGA/ascorbic acid microspheres either act as scavengers of intracellular ROS and/or reduce their formation. Also, the results of antimicrobial activity of PLGA/AgNpPGA/ascorbic acid obtained by the broth microdilution method showed superior and extended activity of these particles. The samples were characterized using Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, zeta potential and particle size analysis. This paper presents a new approach to the treatment of infection that at the same time offers a very pronounced antioxidant effect.",
publisher = "Elsevier",
journal = "Acta Biomaterialia",
title = "Multifunctional PLGA particles containing poly(l-glutamic acid)-capped silver nanoparticles and ascorbic acid with simultaneous antioxidative and prolonged antimicrobial activity",
pages = "151-162",
volume = "10",
number = "1",
doi = "10.1016/j.actbio.2013.08.030"
}
54
51
57

Synthesis of poly(ɛ-caprolactone) nanospheres in the presence of the protective agent poly(glutamic acid) and their cytotoxicity, genotoxicity and ability to induce oxidative stress in HepG2 cells

Filipović, Nenad; Stevanović, Magdalena; Nunić, Jana; Cundrič, Sandra; Filipič, Metka; Uskoković, Dragan

(Elsevier, 2014)

TY  - JOUR
AU  - Filipović, Nenad
AU  - Stevanović, Magdalena
AU  - Nunić, Jana
AU  - Cundrič, Sandra
AU  - Filipič, Metka
AU  - Uskoković, Dragan
PY  - 2014
UR  - http://dais.sanu.ac.rs/123456789/367
AB  - Nanospheres of poly(ɛ-caprolactone) (PCL) with sizes smaller than 200 nm were produced by combining the freeze drying method and the physicochemical solvent/non-solvent approach. The influence of various types of cryoprotectants (poly(glutamic acid) (PGA) or sacharose) and their concentrations on the outcome of freeze-dried poly(ɛ-caprolactone) particles was evaluated. The physiochemical properties, structural and morphological characteristics of thereby obtained PCL particles were determined by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The cytotoxicity of the samples was examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT assay). The formation of intracellular reactive oxygen species was measured spectrophotometrically using a fluorescent probe (DCFH-DA assay). In addition, the genotoxic response of PCL particles obtained using PGA as a cryoprotectant was investigated by the Comet assay. This paper focuses on the role of PGA in the synthesis of PCL particles and demonstrates that PGA plays a dual role in the synthesis, i.e. it acts as a stabilizer but also as a cryoprotective agent. The sufficient and optimal concentration of PGA for producing uniform, spherical but also biocompatible PCL nanoparticles is established to be 0.05%.
PB  - Elsevier
T2  - Colloids and Surfaces B: Biointerfaces
T1  - Synthesis of poly(ɛ-caprolactone) nanospheres in the presence of the protective agent poly(glutamic acid) and their cytotoxicity, genotoxicity and ability to induce oxidative stress in HepG2 cells
SP  - 414
EP  - 424
VL  - 117
IS  - 1
DO  - 10.1016/j.colsurfb.2014.03.015
ER  - 
@article{
author = "Filipović, Nenad and Stevanović, Magdalena and Nunić, Jana and Cundrič, Sandra and Filipič, Metka and Uskoković, Dragan",
year = "2014",
url = "http://dais.sanu.ac.rs/123456789/367",
abstract = "Nanospheres of poly(ɛ-caprolactone) (PCL) with sizes smaller than 200 nm were produced by combining the freeze drying method and the physicochemical solvent/non-solvent approach. The influence of various types of cryoprotectants (poly(glutamic acid) (PGA) or sacharose) and their concentrations on the outcome of freeze-dried poly(ɛ-caprolactone) particles was evaluated. The physiochemical properties, structural and morphological characteristics of thereby obtained PCL particles were determined by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The cytotoxicity of the samples was examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT assay). The formation of intracellular reactive oxygen species was measured spectrophotometrically using a fluorescent probe (DCFH-DA assay). In addition, the genotoxic response of PCL particles obtained using PGA as a cryoprotectant was investigated by the Comet assay. This paper focuses on the role of PGA in the synthesis of PCL particles and demonstrates that PGA plays a dual role in the synthesis, i.e. it acts as a stabilizer but also as a cryoprotective agent. The sufficient and optimal concentration of PGA for producing uniform, spherical but also biocompatible PCL nanoparticles is established to be 0.05%.",
publisher = "Elsevier",
journal = "Colloids and Surfaces B: Biointerfaces",
title = "Synthesis of poly(ɛ-caprolactone) nanospheres in the presence of the protective agent poly(glutamic acid) and their cytotoxicity, genotoxicity and ability to induce oxidative stress in HepG2 cells",
pages = "414-424",
volume = "117",
number = "1",
doi = "10.1016/j.colsurfb.2014.03.015"
}
7
9
10

Synthesis of poly(ɛ-caprolactone) nanospheres in the presence of the protective agent poly(glutamic acid) and their cytotoxicity, genotoxicity and ability to induce oxidative stress in HepG2 cells

Filipović, Nenad; Stevanović, Magdalena; Nunić, Jana; Cundrič, Sandra; Filipič, Metka; Uskoković, Dragan

(Elsevier, 2014)

TY  - JOUR
AU  - Filipović, Nenad
AU  - Stevanović, Magdalena
AU  - Nunić, Jana
AU  - Cundrič, Sandra
AU  - Filipič, Metka
AU  - Uskoković, Dragan
PY  - 2014
UR  - http://dais.sanu.ac.rs/123456789/330
AB  - Nanospheres of poly (ɛ-caprolactone) (PCL) with sizes smaller than 200 nm were produced by combining the freeze drying method and the physicochemical solvent/non-solvent approach. The influence of various types of cryoprotectants (poly(glutamic acid) (PGA) or sacharose) and their concentrations on the outcome of freeze-dried poly(ɛ-caprolactone) particles was evaluated. The physiochemical properties, structural and morphological characteristics of thereby obtained PCL particles were determined by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The cytotoxicity of the samples was examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT assay). The formation of intracellular reactive oxygen species was measured spectrophotometrically using a fluorescent probe (DCFH-DA assay). In addition, the genotoxic response of PCL particles obtained using PGA as a cryoprotectant was investigated by the Comet assay. This paper focuses on the role of PGA in the synthesis of PCL particles and demonstrates that PGA plays a dual role in the synthesis, i.e. it acts as a stabilizer but also as a cryoprotective agent. The sufficient and optimal concentration of PGA for producing uniform, spherical but also biocompatible PCL nanoparticles is established to be 0.05%.
PB  - Elsevier
T2  - Colloids and Surfaces B: Biointerfaces
T1  - Synthesis of poly(ɛ-caprolactone) nanospheres in the presence of the protective agent poly(glutamic acid) and their cytotoxicity, genotoxicity and ability to induce oxidative stress in HepG2 cells
SP  - 414
EP  - 424
VL  - 117
IS  - 1
DO  - 10.1016/j.colsurfb.2014.03.015
ER  - 
@article{
author = "Filipović, Nenad and Stevanović, Magdalena and Nunić, Jana and Cundrič, Sandra and Filipič, Metka and Uskoković, Dragan",
year = "2014",
url = "http://dais.sanu.ac.rs/123456789/330",
abstract = "Nanospheres of poly (ɛ-caprolactone) (PCL) with sizes smaller than 200 nm were produced by combining the freeze drying method and the physicochemical solvent/non-solvent approach. The influence of various types of cryoprotectants (poly(glutamic acid) (PGA) or sacharose) and their concentrations on the outcome of freeze-dried poly(ɛ-caprolactone) particles was evaluated. The physiochemical properties, structural and morphological characteristics of thereby obtained PCL particles were determined by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The cytotoxicity of the samples was examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT assay). The formation of intracellular reactive oxygen species was measured spectrophotometrically using a fluorescent probe (DCFH-DA assay). In addition, the genotoxic response of PCL particles obtained using PGA as a cryoprotectant was investigated by the Comet assay. This paper focuses on the role of PGA in the synthesis of PCL particles and demonstrates that PGA plays a dual role in the synthesis, i.e. it acts as a stabilizer but also as a cryoprotective agent. The sufficient and optimal concentration of PGA for producing uniform, spherical but also biocompatible PCL nanoparticles is established to be 0.05%.",
publisher = "Elsevier",
journal = "Colloids and Surfaces B: Biointerfaces",
title = "Synthesis of poly(ɛ-caprolactone) nanospheres in the presence of the protective agent poly(glutamic acid) and their cytotoxicity, genotoxicity and ability to induce oxidative stress in HepG2 cells",
pages = "414-424",
volume = "117",
number = "1",
doi = "10.1016/j.colsurfb.2014.03.015"
}
7
9
10

Development of lyophilized spherical particles of poly(epsilon-caprolactone) and examination of their morphology, cytocompatibility and influence on the formation of reactive oxygen species

Stupar, Petar; Pavlović, Vladimir B.; Nunić, Jana; Cundrič, Sandra; Filipič, Metka; Stevanović, Magdalena

(Paris : Association de pharmacie galenique industrielle, 2014)

TY  - JOUR
AU  - Stupar, Petar
AU  - Pavlović, Vladimir B.
AU  - Nunić, Jana
AU  - Cundrič, Sandra
AU  - Filipič, Metka
AU  - Stevanović, Magdalena
PY  - 2014
UR  - http://dais.sanu.ac.rs/123456789/425
AB  - A common limitation of using polymeric micro- and nanoparticles in long-term conservation is due to their poor physical and chemical stability. Freeze-drying is one of the most convenient methods that enable further reconstitution of micro- and nanoparticles for therapeutical use. Nevertheless, this process generates various stresses during freezing and desiccation steps. This paper underlines the combined outcomes of freeze drying method and physicochemical solvent/non-solvent approach to design biocompatible poly(epsilon-caprolactone) (PCL) nanospheres and evaluate influence of different cryoprotectants (glucose, saccharose, polyvinyl alcohol or polyglutamic acid) on the outcome of freeze-dried PCL particles. Samples were characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and dynamic light scattering method (DLS). In vitro studies used, include MTT assay (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), testing cytotoxicity as the quality of being toxic to cells, and DCFHDA assay (2’,7’-dichlordihydrofluorescein-diacetate), testing the possible increase in ROS levels. It was found that cryoprotection with 1% glucose solution is an optimal for obtaining uniform, spherical but also biocompatible PCL nanoparticles for biomedical purposes.
PB  - Paris : Association de pharmacie galenique industrielle
T2  - Journal of Drug Delivery Science and Technology
T1  - Development of lyophilized spherical particles of poly(epsilon-caprolactone) and examination of their morphology, cytocompatibility and influence on the formation of reactive oxygen species
SP  - 191
EP  - 197
VL  - 24
IS  - 2
DO  - 10.1016/S1773-2247(14)50031-7
ER  - 
@article{
author = "Stupar, Petar and Pavlović, Vladimir B. and Nunić, Jana and Cundrič, Sandra and Filipič, Metka and Stevanović, Magdalena",
year = "2014",
url = "http://dais.sanu.ac.rs/123456789/425",
abstract = "A common limitation of using polymeric micro- and nanoparticles in long-term conservation is due to their poor physical and chemical stability. Freeze-drying is one of the most convenient methods that enable further reconstitution of micro- and nanoparticles for therapeutical use. Nevertheless, this process generates various stresses during freezing and desiccation steps. This paper underlines the combined outcomes of freeze drying method and physicochemical solvent/non-solvent approach to design biocompatible poly(epsilon-caprolactone) (PCL) nanospheres and evaluate influence of different cryoprotectants (glucose, saccharose, polyvinyl alcohol or polyglutamic acid) on the outcome of freeze-dried PCL particles. Samples were characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and dynamic light scattering method (DLS). In vitro studies used, include MTT assay (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), testing cytotoxicity as the quality of being toxic to cells, and DCFHDA assay (2’,7’-dichlordihydrofluorescein-diacetate), testing the possible increase in ROS levels. It was found that cryoprotection with 1% glucose solution is an optimal for obtaining uniform, spherical but also biocompatible PCL nanoparticles for biomedical purposes.",
publisher = "Paris : Association de pharmacie galenique industrielle",
journal = "Journal of Drug Delivery Science and Technology",
title = "Development of lyophilized spherical particles of poly(epsilon-caprolactone) and examination of their morphology, cytocompatibility and influence on the formation of reactive oxygen species",
pages = "191-197",
volume = "24",
number = "2",
doi = "10.1016/S1773-2247(14)50031-7"
}
4
3
4

Development of lyophilized spherical particles of poly(epsilon-caprolactone) and examination of their morphology, cytocompatibility and influence on the formation of reactive oxygen species

Stupar, Petar; Pavlović, Vladimir B.; Nunić, Jana; Cundrič, Sandra; Filipič, Metka; Stevanović, Magdalena

(Paris : Association de pharmacie galenique industrielle, 2014)

TY  - JOUR
AU  - Stupar, Petar
AU  - Pavlović, Vladimir B.
AU  - Nunić, Jana
AU  - Cundrič, Sandra
AU  - Filipič, Metka
AU  - Stevanović, Magdalena
PY  - 2014
UR  - http://dais.sanu.ac.rs/123456789/4671
AB  - A common limitation of using polymeric micro- and nanoparticles in long-term conservation is due to their poor physical and chemical stability. Freeze-drying is one of the most convenient methods that enable further reconstitution of micro- and nanoparticles for therapeutical use. Nevertheless, this process generates various stresses during freezing and desiccation steps. This paper underlines the combined outcomes of freeze drying method and physicochemical solvent/non-solvent approach to design biocompatible poly(epsilon-caprolactone) (PCL) nanospheres and evaluate influence of different cryoprotectants (glucose, saccharose, polyvinyl alcohol or polyglutamic acid) on the outcome of freeze-dried PCL particles. Samples were characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and dynamic light scattering method (DLS). In vitro studies used, include MTT assay (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), testing cytotoxicity as the quality of being toxic to cells, and DCFHDA assay (2’,7’-dichlordihydrofluorescein-diacetate), testing the possible increase in ROS levels. It was found that cryoprotection with 1% glucose solution is an optimal for obtaining uniform, spherical but also biocompatible PCL nanoparticles for biomedical purposes.
PB  - Paris : Association de pharmacie galenique industrielle
T2  - Journal of Drug Delivery Science and Technology
T1  - Development of lyophilized spherical particles of poly(epsilon-caprolactone) and examination of their morphology, cytocompatibility and influence on the formation of reactive oxygen species
SP  - 191
EP  - 197
VL  - 24
IS  - 2
DO  - 10.1016/S1773-2247(14)50031-7
ER  - 
@article{
author = "Stupar, Petar and Pavlović, Vladimir B. and Nunić, Jana and Cundrič, Sandra and Filipič, Metka and Stevanović, Magdalena",
year = "2014",
url = "http://dais.sanu.ac.rs/123456789/4671",
abstract = "A common limitation of using polymeric micro- and nanoparticles in long-term conservation is due to their poor physical and chemical stability. Freeze-drying is one of the most convenient methods that enable further reconstitution of micro- and nanoparticles for therapeutical use. Nevertheless, this process generates various stresses during freezing and desiccation steps. This paper underlines the combined outcomes of freeze drying method and physicochemical solvent/non-solvent approach to design biocompatible poly(epsilon-caprolactone) (PCL) nanospheres and evaluate influence of different cryoprotectants (glucose, saccharose, polyvinyl alcohol or polyglutamic acid) on the outcome of freeze-dried PCL particles. Samples were characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and dynamic light scattering method (DLS). In vitro studies used, include MTT assay (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), testing cytotoxicity as the quality of being toxic to cells, and DCFHDA assay (2’,7’-dichlordihydrofluorescein-diacetate), testing the possible increase in ROS levels. It was found that cryoprotection with 1% glucose solution is an optimal for obtaining uniform, spherical but also biocompatible PCL nanoparticles for biomedical purposes.",
publisher = "Paris : Association de pharmacie galenique industrielle",
journal = "Journal of Drug Delivery Science and Technology",
title = "Development of lyophilized spherical particles of poly(epsilon-caprolactone) and examination of their morphology, cytocompatibility and influence on the formation of reactive oxygen species",
pages = "191-197",
volume = "24",
number = "2",
doi = "10.1016/S1773-2247(14)50031-7"
}
4
3
4

Poly(lactide-co-glycolide)/silver nanoparticles: Synthesis, characterization, antimicrobial activity, cytotoxicity assessment and ROS-inducing potential

Stevanović, Magdalena; Škapin, Srečo Davor; Bračko, Ines; Milenković, Marina; Petković, Jana; Filipič, Metka; Uskoković, Dragan

(Elsevier, 2012)

TY  - JOUR
AU  - Stevanović, Magdalena
AU  - Škapin, Srečo Davor
AU  - Bračko, Ines
AU  - Milenković, Marina
AU  - Petković, Jana
AU  - Filipič, Metka
AU  - Uskoković, Dragan
PY  - 2012
UR  - http://dais.sanu.ac.rs/123456789/488
AB  - Silver nanoparticles (AgNps) were prepared by modified chemical reduction with poly (α, γ, l-glutamic acid) (PGA) as capping agent. These Ag/PGA nanoparticles (AgNpPGAs) were highly stable over long periods of time without signs of precipitation. In addition to obtaining stable AgNpPGAs, a further aim was to examine their encapsulation in the poly(L-lactide-co-glycolide) (PLGA) polymer matrix. The current interest of polymer-AgNps in biomedical applications is because a versatile system must have antimicrobial activity upon target contact, without the release of toxic biocides. The synthesis of these PLGA/AgNpPGAs used physicochemical methods with solvent/non-solvent systems. Degradation of these PLGA/AgNpPGAs and the release rate of their AgNPs were studied in physiological solution over three months. The antimicrobial activity of the samples was investigated towards six laboratory control strains from the American Type Culture Collection (ATCC) and one clinical isolate methicillin-resistant Staphylococcus aureus strain by the broth microdilution method and the results showed superior and extended activity of PLGA/AgNpPGAs. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay indicated good biocompatibility of these PLGA/AgNpPGAs. The formation of intracellular reactive oxygen species was measured spectrophotometrically using a fluorescent probe, which showed that these PLGA/AgNpPGAs are not inducers of such species. The samples were characterized by UV–VIS spectrometry, X-ray diffraction, zeta potential measurements, field-emission scanning electron microscopy, and transmission electron microscopy.
PB  - Elsevier
T2  - Polymer
T1  - Poly(lactide-co-glycolide)/silver nanoparticles: Synthesis, characterization, antimicrobial activity, cytotoxicity assessment and ROS-inducing potential
SP  - 2818
EP  - 2828
VL  - 53
IS  - 14
DO  - 10.1016/j.polymer.2012.04.057
ER  - 
@article{
author = "Stevanović, Magdalena and Škapin, Srečo Davor and Bračko, Ines and Milenković, Marina and Petković, Jana and Filipič, Metka and Uskoković, Dragan",
year = "2012",
url = "http://dais.sanu.ac.rs/123456789/488",
abstract = "Silver nanoparticles (AgNps) were prepared by modified chemical reduction with poly (α, γ, l-glutamic acid) (PGA) as capping agent. These Ag/PGA nanoparticles (AgNpPGAs) were highly stable over long periods of time without signs of precipitation. In addition to obtaining stable AgNpPGAs, a further aim was to examine their encapsulation in the poly(L-lactide-co-glycolide) (PLGA) polymer matrix. The current interest of polymer-AgNps in biomedical applications is because a versatile system must have antimicrobial activity upon target contact, without the release of toxic biocides. The synthesis of these PLGA/AgNpPGAs used physicochemical methods with solvent/non-solvent systems. Degradation of these PLGA/AgNpPGAs and the release rate of their AgNPs were studied in physiological solution over three months. The antimicrobial activity of the samples was investigated towards six laboratory control strains from the American Type Culture Collection (ATCC) and one clinical isolate methicillin-resistant Staphylococcus aureus strain by the broth microdilution method and the results showed superior and extended activity of PLGA/AgNpPGAs. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay indicated good biocompatibility of these PLGA/AgNpPGAs. The formation of intracellular reactive oxygen species was measured spectrophotometrically using a fluorescent probe, which showed that these PLGA/AgNpPGAs are not inducers of such species. The samples were characterized by UV–VIS spectrometry, X-ray diffraction, zeta potential measurements, field-emission scanning electron microscopy, and transmission electron microscopy.",
publisher = "Elsevier",
journal = "Polymer",
title = "Poly(lactide-co-glycolide)/silver nanoparticles: Synthesis, characterization, antimicrobial activity, cytotoxicity assessment and ROS-inducing potential",
pages = "2818-2828",
volume = "53",
number = "14",
doi = "10.1016/j.polymer.2012.04.057"
}
53
53
55

Enhanced antimicrobial efficacy by co-delivery of PGA capped silver nanoparticles and ascorbic acid with poly(lactide-co-glycolide)

Stevanović, Magdalena; Milenković, Marina; Petković, Jana; Filipič, Metka; Uskoković, Dragan

(Belgrade : Materials Research Society of Serbia, 2012)

TY  - CONF
AU  - Stevanović, Magdalena
AU  - Milenković, Marina
AU  - Petković, Jana
AU  - Filipič, Metka
AU  - Uskoković, Dragan
PY  - 2012
UR  - http://dais.sanu.ac.rs/123456789/457
AB  - Silver nanoparticles (AgNps) were prepared by modified chemical reduction with poly (Lglutamic acid) (PGA) as capping agent. These Ag/PGA nanoparticles (AgNpPGAs) were highly stable over the long periods of time without signs of precipitation. Ascorbic acid, a water soluble antioxidant, was encapsulated together with these stable AgNpPGAs within poly(DL-lactide-coglycolide) polymeric matrix and their synergistic antimicrobial effect was studied. The antimicrobial activity of the samples was investigated towards six laboratory control strains from the American Type Culture Collection (ATCC) and one clinical isolate methicillin-resistant Staphylococcus aureus strain by the broth microdilution method. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay indicated good biocompatibility of the samples. To establish the influence of PLGA/AgNpPGA/ascorbic acid nanoparticles on intracellular ROS formation, we measured the kinetics of their formation in HepG2 cells by DCFH-DA assay. The samples were characterized by UV-VIS spectrometry, field-emission scanning electron microscopy, and transmission electron microscopy.
PB  - Belgrade : Materials Research Society of Serbia
C3  - The Fourteenth Annual Conference YUCOMAT 2012: Programme and the Book of Abstracts
T1  - Enhanced antimicrobial efficacy by co-delivery of PGA capped silver nanoparticles and ascorbic acid with poly(lactide-co-glycolide)
SP  - 124
EP  - 124
ER  - 
@conference{
author = "Stevanović, Magdalena and Milenković, Marina and Petković, Jana and Filipič, Metka and Uskoković, Dragan",
year = "2012",
url = "http://dais.sanu.ac.rs/123456789/457",
abstract = "Silver nanoparticles (AgNps) were prepared by modified chemical reduction with poly (Lglutamic acid) (PGA) as capping agent. These Ag/PGA nanoparticles (AgNpPGAs) were highly stable over the long periods of time without signs of precipitation. Ascorbic acid, a water soluble antioxidant, was encapsulated together with these stable AgNpPGAs within poly(DL-lactide-coglycolide) polymeric matrix and their synergistic antimicrobial effect was studied. The antimicrobial activity of the samples was investigated towards six laboratory control strains from the American Type Culture Collection (ATCC) and one clinical isolate methicillin-resistant Staphylococcus aureus strain by the broth microdilution method. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay indicated good biocompatibility of the samples. To establish the influence of PLGA/AgNpPGA/ascorbic acid nanoparticles on intracellular ROS formation, we measured the kinetics of their formation in HepG2 cells by DCFH-DA assay. The samples were characterized by UV-VIS spectrometry, field-emission scanning electron microscopy, and transmission electron microscopy.",
publisher = "Belgrade : Materials Research Society of Serbia",
journal = "The Fourteenth Annual Conference YUCOMAT 2012: Programme and the Book of Abstracts",
title = "Enhanced antimicrobial efficacy by co-delivery of PGA capped silver nanoparticles and ascorbic acid with poly(lactide-co-glycolide)",
pages = "124-124"
}

Freeze-drying method to produce a range of PCL particles with tailored morphological properties

Filipović, Nenad; Stevanović, Magdalena; Stupar, Petar; Petković, Jana; Filipič, Metka; Uskoković, Dragan

(Belgrade : Materials Research Society of Serbia, 2012)

TY  - CONF
AU  - Filipović, Nenad
AU  - Stevanović, Magdalena
AU  - Stupar, Petar
AU  - Petković, Jana
AU  - Filipič, Metka
AU  - Uskoković, Dragan
PY  - 2012
UR  - http://dais.sanu.ac.rs/123456789/456
AB  - Poly (ε-caprolactone) (PCL) is a widely investigated bioresorbable polymer and it has been extensively used in numerous biomaterials applications especially in tissue engineering and drug delivery systems. Freeze-dried particles of poly (ε-caprolactone), with different morphological characteristics (spherical or cube in shape), were prepared by physicochemical method with solvent/non-solvent systems and by using the different types of cryoprotectants. Natural polymer poly (L-glutamic acid) (PGA) as well as disaccharide, saccharose, were used as cryoprotectant i.e. substance that is used to protect particles from freezing damage (damage due to ice formation). PGA has dual role in the synthesis; besides as cryoprotectant, it acts as stabilizer of the particles i.e. to prevent their agglomeration. The samples were characterized by Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). The biocompatibility of the samples was examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The formation of intracellular reactive oxygen species was measured spectrophotometrically using a fluorescent probe.
PB  - Belgrade : Materials Research Society of Serbia
C3  - The Fourteenth Annual Conference YUCOMAT 2012: Programme and the Book of Abstracts
T1  - Freeze-drying method to produce a range of PCL particles with tailored morphological properties
SP  - 124
EP  - 124
ER  - 
@conference{
author = "Filipović, Nenad and Stevanović, Magdalena and Stupar, Petar and Petković, Jana and Filipič, Metka and Uskoković, Dragan",
year = "2012",
url = "http://dais.sanu.ac.rs/123456789/456",
abstract = "Poly (ε-caprolactone) (PCL) is a widely investigated bioresorbable polymer and it has been extensively used in numerous biomaterials applications especially in tissue engineering and drug delivery systems. Freeze-dried particles of poly (ε-caprolactone), with different morphological characteristics (spherical or cube in shape), were prepared by physicochemical method with solvent/non-solvent systems and by using the different types of cryoprotectants. Natural polymer poly (L-glutamic acid) (PGA) as well as disaccharide, saccharose, were used as cryoprotectant i.e. substance that is used to protect particles from freezing damage (damage due to ice formation). PGA has dual role in the synthesis; besides as cryoprotectant, it acts as stabilizer of the particles i.e. to prevent their agglomeration. The samples were characterized by Fourier transform infrared spectroscopy (FTIR) and Scanning electron microscopy (SEM). The biocompatibility of the samples was examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The formation of intracellular reactive oxygen species was measured spectrophotometrically using a fluorescent probe.",
publisher = "Belgrade : Materials Research Society of Serbia",
journal = "The Fourteenth Annual Conference YUCOMAT 2012: Programme and the Book of Abstracts",
title = "Freeze-drying method to produce a range of PCL particles with tailored morphological properties",
pages = "124-124"
}

Effects of different cryoprotectants on morphology of lyophilized poly(ε-caprolactone) micro and nanospheres

Stupar, Petar; Stevanović, Magdalena; Filipović, Nenad; Pavlović, Vladimir B.; Nunić, Jana; Cundrič, Sandra; Filipič, Metka; Uskoković, Dragan

(Belgrade : Materials Research Society of Serbia; Institute of Technical Sciences of SASA; Vinča Institute of Nuclear Sciences, University of Belgrade, 2012)

TY  - CONF
AU  - Stupar, Petar
AU  - Stevanović, Magdalena
AU  - Filipović, Nenad
AU  - Pavlović, Vladimir B.
AU  - Nunić, Jana
AU  - Cundrič, Sandra
AU  - Filipič, Metka
AU  - Uskoković, Dragan
PY  - 2012
UR  - http://dais.sanu.ac.rs/123456789/531
AB  - A common limitation of using polymeric micro and nanoparticles in long-term conservation is due to their poor physical and chemical stability. Freeze-drying is one of the most convenient methods that enable further reconstitution of micro and nanoparticles for therapeutical use. Nevertheless, this process generates various stresses during freezing and desiccation steps. The aim of this study was to evaluate different cryoprotectants (protective excipients that are usually added to increase stability upon storage and protect the particles from freezing stress): sugars (glucose and sucrose) and polymers (PVA and PGA), on the outcome of freeze-dried poly(ε-caprolactone) micro and nanospheres. The best freeze-drying results in terms of morphological characteristics, analyzed with SEM, were achieved with glucose at concentration of 1%. The FTIR analysis confirmed that the molecular structure of PCL particles remained the same after the addition cryoprotectants.
PB  - Belgrade : Materials Research Society of Serbia; Institute of Technical Sciences of SASA; Vinča Institute of Nuclear Sciences, University of Belgrade
C3  - Joint Event of the 11th Young Researchers’ Conference: Materials Science and Engineering and the 1st European Early Stage Researches’ Conference on Hydrogen Storage: Program and the Book of Abstracts
T1  - Effects of different cryoprotectants on morphology of lyophilized poly(ε-caprolactone) micro and nanospheres
SP  - 104
EP  - 104
ER  - 
@conference{
author = "Stupar, Petar and Stevanović, Magdalena and Filipović, Nenad and Pavlović, Vladimir B. and Nunić, Jana and Cundrič, Sandra and Filipič, Metka and Uskoković, Dragan",
year = "2012",
url = "http://dais.sanu.ac.rs/123456789/531",
abstract = "A common limitation of using polymeric micro and nanoparticles in long-term conservation is due to their poor physical and chemical stability. Freeze-drying is one of the most convenient methods that enable further reconstitution of micro and nanoparticles for therapeutical use. Nevertheless, this process generates various stresses during freezing and desiccation steps. The aim of this study was to evaluate different cryoprotectants (protective excipients that are usually added to increase stability upon storage and protect the particles from freezing stress): sugars (glucose and sucrose) and polymers (PVA and PGA), on the outcome of freeze-dried poly(ε-caprolactone) micro and nanospheres. The best freeze-drying results in terms of morphological characteristics, analyzed with SEM, were achieved with glucose at concentration of 1%. The FTIR analysis confirmed that the molecular structure of PCL particles remained the same after the addition cryoprotectants.",
publisher = "Belgrade : Materials Research Society of Serbia; Institute of Technical Sciences of SASA; Vinča Institute of Nuclear Sciences, University of Belgrade",
journal = "Joint Event of the 11th Young Researchers’ Conference: Materials Science and Engineering and the 1st European Early Stage Researches’ Conference on Hydrogen Storage: Program and the Book of Abstracts",
title = "Effects of different cryoprotectants on morphology of lyophilized poly(ε-caprolactone) micro and nanospheres",
pages = "104-104"
}

DNA damage and alterations in expression of DNA damage responsive genes induced by TiO2 nanoparticles in human hepatoma HepG2 cells

Petković, Jana; Žegura, Bojana; Stevanović, Magdalena; Drnovšek, Nataša; Uskoković, Dragan; Novak, Saša; Filipič, Metka

(Oxon : Taylor & Francis, 2011)

TY  - JOUR
AU  - Petković, Jana
AU  - Žegura, Bojana
AU  - Stevanović, Magdalena
AU  - Drnovšek, Nataša
AU  - Uskoković, Dragan
AU  - Novak, Saša
AU  - Filipič, Metka
PY  - 2011
UR  - http://dais.sanu.ac.rs/123456789/568
AB  - We investigated the genotoxic responses to two types of TiO2 nanoparticles (<25 nm anatase: TiO2-An, and <100 nm rutile: TiO2-Ru) in human hepatoma HepG2 cells. Under the applied exposure conditions the particles were agglomerated or aggregated with the size of agglomerates and aggregates in the micrometer range, and were not cytotoxic. TiO2-An, but not TiO2-Ru, caused a persistent increase in DNA strand breaks (comet assay) and oxidized purines (Fpg-comet). TiO2-An was a stronger inducer of intracellular reactive oxygen species (ROS) than TiO2-Ru. Both types of TiO2 nanoparticles transiently upregulated mRNA expression of p53 and its downstream regulated DNA damage responsive genes (mdm2, gadd45α, p21), providing additional evidence that TiO2 nanoparticles are genotoxic. The observed differences in responses of HepG2 cells to exposure to anatase and rutile TiO2 nanoparticles support the evidence that the toxic potential of TiO2 nanoparticles varies not only with particle size but also with crystalline structure.
PB  - Oxon : Taylor & Francis
T2  - Nanotoxicology
T1  - DNA damage and alterations in expression of DNA damage responsive genes induced by TiO2 nanoparticles in human hepatoma HepG2 cells
SP  - 341
EP  - 353
VL  - 5
IS  - 3
DO  - 10.3109/17435390.2010.507316
ER  - 
@article{
author = "Petković, Jana and Žegura, Bojana and Stevanović, Magdalena and Drnovšek, Nataša and Uskoković, Dragan and Novak, Saša and Filipič, Metka",
year = "2011",
url = "http://dais.sanu.ac.rs/123456789/568",
abstract = "We investigated the genotoxic responses to two types of TiO2 nanoparticles (<25 nm anatase: TiO2-An, and <100 nm rutile: TiO2-Ru) in human hepatoma HepG2 cells. Under the applied exposure conditions the particles were agglomerated or aggregated with the size of agglomerates and aggregates in the micrometer range, and were not cytotoxic. TiO2-An, but not TiO2-Ru, caused a persistent increase in DNA strand breaks (comet assay) and oxidized purines (Fpg-comet). TiO2-An was a stronger inducer of intracellular reactive oxygen species (ROS) than TiO2-Ru. Both types of TiO2 nanoparticles transiently upregulated mRNA expression of p53 and its downstream regulated DNA damage responsive genes (mdm2, gadd45α, p21), providing additional evidence that TiO2 nanoparticles are genotoxic. The observed differences in responses of HepG2 cells to exposure to anatase and rutile TiO2 nanoparticles support the evidence that the toxic potential of TiO2 nanoparticles varies not only with particle size but also with crystalline structure.",
publisher = "Oxon : Taylor & Francis",
journal = "Nanotoxicology",
title = "DNA damage and alterations in expression of DNA damage responsive genes induced by TiO2 nanoparticles in human hepatoma HepG2 cells",
pages = "341-353",
volume = "5",
number = "3",
doi = "10.3109/17435390.2010.507316"
}
156
147
151

Effect of poly-α, γ, L-glutamic acid as a capping agent on morphology and oxidative stress-dependent toxicity of silver nanoparticles

Stevanović, Magdalena; Kovačević, Branimir; Petković, Jana; Filipič, Metka; Uskoković, Dragan

(Dove Medical Press, 2011)

TY  - JOUR
AU  - Stevanović, Magdalena
AU  - Kovačević, Branimir
AU  - Petković, Jana
AU  - Filipič, Metka
AU  - Uskoković, Dragan
PY  - 2011
UR  - http://dais.sanu.ac.rs/123456789/900
AB  - Highly stable dispersions of nanosized silver particles were synthesized using a straightforward, cost-effective, and ecofriendly method. Nontoxic glucose was utilized as a reducing agent and poly- α, γ, L-glutamic acid (PGA), a naturally occurring anionic polymer, was used as a capping agent to protect the silver nanoparticles from agglomeration and render them biocompatible. Use of ammonia during synthesis was avoided. Our study clearly demonstrates how the concentration of the capping agent plays a major role in determining the dimensions, morphology, and stability, as well as toxicity of a silver colloidal solution. Hence, proper optimization is necessary to develop silver colloids of narrow size distribution. The samples were characterized by Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, and zeta potential measurement. MTT assay results indicated good biocompatibility of the PGA-capped silver nanoparticles. Formation of intracellular reactive oxygen species was measured spectrophotometrically using 2,7-dichlorofluorescein diacetate as a fluorescent probe, and it was shown that the PGA-capped silver nanoparticles did not induce intracellular formation of reactive oxygen species.
PB  - Dove Medical Press
T2  - International Journal of Nanomedicine
T1  - Effect of poly-α, γ, L-glutamic acid as a capping agent on morphology and oxidative stress-dependent toxicity of silver nanoparticles
SP  - 2837
EP  - 2837
DO  - 10.2147/IJN.S24889
ER  - 
@article{
author = "Stevanović, Magdalena and Kovačević, Branimir and Petković, Jana and Filipič, Metka and Uskoković, Dragan",
year = "2011",
url = "http://dais.sanu.ac.rs/123456789/900",
abstract = "Highly stable dispersions of nanosized silver particles were synthesized using a straightforward, cost-effective, and ecofriendly method. Nontoxic glucose was utilized as a reducing agent and poly- α, γ, L-glutamic acid (PGA), a naturally occurring anionic polymer, was used as a capping agent to protect the silver nanoparticles from agglomeration and render them biocompatible. Use of ammonia during synthesis was avoided. Our study clearly demonstrates how the concentration of the capping agent plays a major role in determining the dimensions, morphology, and stability, as well as toxicity of a silver colloidal solution. Hence, proper optimization is necessary to develop silver colloids of narrow size distribution. The samples were characterized by Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, and zeta potential measurement. MTT assay results indicated good biocompatibility of the PGA-capped silver nanoparticles. Formation of intracellular reactive oxygen species was measured spectrophotometrically using 2,7-dichlorofluorescein diacetate as a fluorescent probe, and it was shown that the PGA-capped silver nanoparticles did not induce intracellular formation of reactive oxygen species.",
publisher = "Dove Medical Press",
journal = "International Journal of Nanomedicine",
title = "Effect of poly-α, γ, L-glutamic acid as a capping agent on morphology and oxidative stress-dependent toxicity of silver nanoparticles",
pages = "2837-2837",
doi = "10.2147/IJN.S24889"
}
32
32
34

DNA damage and alterations in expression of DNA damage responsive genes induced by TiO2 nanoparticles in human hepatoma HepG2 cells

Petković, Jana; Žegura, Bojana; Stevanović, Magdalena; Drnovšek, Nataša; Uskoković, Dragan; Novak, Saša; Filipič, Metka

(Oxon : Taylor & Francis, 2011)

TY  - JOUR
AU  - Petković, Jana
AU  - Žegura, Bojana
AU  - Stevanović, Magdalena
AU  - Drnovšek, Nataša
AU  - Uskoković, Dragan
AU  - Novak, Saša
AU  - Filipič, Metka
PY  - 2011
UR  - http://dais.sanu.ac.rs/123456789/4672
AB  - We investigated the genotoxic responses to two types of TiO2 nanoparticles (<25 nm anatase: TiO2-An, and <100 nm rutile: TiO2-Ru) in human hepatoma HepG2 cells. Under the applied exposure conditions the particles were agglomerated or aggregated with the size of agglomerates and aggregates in the micrometer range, and were not cytotoxic. TiO2-An, but not TiO2-Ru, caused a persistent increase in DNA strand breaks (comet assay) and oxidized purines (Fpg-comet). TiO2-An was a stronger inducer of intracellular reactive oxygen species (ROS) than TiO2-Ru. Both types of TiO2 nanoparticles transiently upregulated mRNA expression of p53 and its downstream regulated DNA damage responsive genes (mdm2, gadd45α, p21), providing additional evidence that TiO2 nanoparticles are genotoxic. The observed differences in responses of HepG2 cells to exposure to anatase and rutile TiO2 nanoparticles support the evidence that the toxic potential of TiO2 nanoparticles varies not only with particle size but also with crystalline structure.
PB  - Oxon : Taylor & Francis
T2  - Nanotoxicology
T1  - DNA damage and alterations in expression of DNA damage responsive genes induced by TiO2 nanoparticles in human hepatoma HepG2 cells
SP  - 341
EP  - 353
VL  - 5
IS  - 3
DO  - 10.3109/17435390.2010.507316
ER  - 
@article{
author = "Petković, Jana and Žegura, Bojana and Stevanović, Magdalena and Drnovšek, Nataša and Uskoković, Dragan and Novak, Saša and Filipič, Metka",
year = "2011",
url = "http://dais.sanu.ac.rs/123456789/4672",
abstract = "We investigated the genotoxic responses to two types of TiO2 nanoparticles (<25 nm anatase: TiO2-An, and <100 nm rutile: TiO2-Ru) in human hepatoma HepG2 cells. Under the applied exposure conditions the particles were agglomerated or aggregated with the size of agglomerates and aggregates in the micrometer range, and were not cytotoxic. TiO2-An, but not TiO2-Ru, caused a persistent increase in DNA strand breaks (comet assay) and oxidized purines (Fpg-comet). TiO2-An was a stronger inducer of intracellular reactive oxygen species (ROS) than TiO2-Ru. Both types of TiO2 nanoparticles transiently upregulated mRNA expression of p53 and its downstream regulated DNA damage responsive genes (mdm2, gadd45α, p21), providing additional evidence that TiO2 nanoparticles are genotoxic. The observed differences in responses of HepG2 cells to exposure to anatase and rutile TiO2 nanoparticles support the evidence that the toxic potential of TiO2 nanoparticles varies not only with particle size but also with crystalline structure.",
publisher = "Oxon : Taylor & Francis",
journal = "Nanotoxicology",
title = "DNA damage and alterations in expression of DNA damage responsive genes induced by TiO2 nanoparticles in human hepatoma HepG2 cells",
pages = "341-353",
volume = "5",
number = "3",
doi = "10.3109/17435390.2010.507316"
}
156
147
151

An innovative, quick and convenient labeling method for the investigation of pharmacological behavior and the metabolism of poly(DL-lactide-co-glycolide) nanospheres

Stevanović, Magdalena; Maksin, Tatjana; Petković, Jana; Filipič, Metka; Uskoković, Dragan

(Bristol : IOP Science, 2009)

TY  - JOUR
AU  - Stevanović, Magdalena
AU  - Maksin, Tatjana
AU  - Petković, Jana
AU  - Filipič, Metka
AU  - Uskoković, Dragan
PY  - 2009
UR  - http://dais.sanu.ac.rs/123456789/2740
AB  - Nanoparticles of poly(DL-lactide-co-glycolide) (PLGA) in the size range 90-150 nm were produced using the physicochemical method with solvent/non-solvent systems. The encapsulation of the ascorbic acid in the polymer matrix was performed by homogenization of the water and organic phases. In vitro degradation and release tests of PLGA nanoparticles with and without encapsulated ascorbic acid were studied for more than 60 days in PBS and it has been determined that PLGA completely degrades within this period, fully releasing all encapsulated ascorbic acid. The cytotoxicity of PLGA and PLGA/ascorbic acid 85/15% nanoparticles was examined with human hepatoma cell lines (HepG2 ECACC), in vitro. The obtained results indicate that neither PLGA nanospheres nor PLGA/ascorbic acid 85/15% nanoparticles significantly affected the viability of the HepG2 cells. The investigation of the distribution and pharmacokinetics of PLGA is crucial for the effective prediction of host responses to PLGA in particular applications. Thus we present a method of labeling PLGA nanospheres and PLGA/ascorbic acid 85/15 wt% nanoparticles by (99m)Tc which binds outside, leaving the cage intact. This enables a quick and convenient investigation of the pharmacological behavior and metabolism of PLGA. The biodistribution of (99m)Tc-labeled PLGA particles with and without encapsulated ascorbic acid after different periods of time of their installation into rats was examined. PLGA nanospheres with encapsulated ascorbic acid exhibit prolonged blood circulation accompanied by time-dependent reduction in the lungs, liver and spleen, and addition in the kidney, stomach and intestine. The samples were characterized by x-ray diffraction, scanning electron microscopy, stereological analysis, transmission electron microscopy, ultraviolet spectroscopy and instant thin layer chromatography.
PB  - Bristol : IOP Science
T2  - Nanotechnology
T1  - An innovative, quick and convenient labeling method for the investigation of pharmacological behavior and the metabolism of poly(DL-lactide-co-glycolide) nanospheres
VL  - 20
IS  - 33
DO  - 10.1088/0957-4484/20/33/335102
ER  - 
@article{
author = "Stevanović, Magdalena and Maksin, Tatjana and Petković, Jana and Filipič, Metka and Uskoković, Dragan",
year = "2009",
url = "http://dais.sanu.ac.rs/123456789/2740",
abstract = "Nanoparticles of poly(DL-lactide-co-glycolide) (PLGA) in the size range 90-150 nm were produced using the physicochemical method with solvent/non-solvent systems. The encapsulation of the ascorbic acid in the polymer matrix was performed by homogenization of the water and organic phases. In vitro degradation and release tests of PLGA nanoparticles with and without encapsulated ascorbic acid were studied for more than 60 days in PBS and it has been determined that PLGA completely degrades within this period, fully releasing all encapsulated ascorbic acid. The cytotoxicity of PLGA and PLGA/ascorbic acid 85/15% nanoparticles was examined with human hepatoma cell lines (HepG2 ECACC), in vitro. The obtained results indicate that neither PLGA nanospheres nor PLGA/ascorbic acid 85/15% nanoparticles significantly affected the viability of the HepG2 cells. The investigation of the distribution and pharmacokinetics of PLGA is crucial for the effective prediction of host responses to PLGA in particular applications. Thus we present a method of labeling PLGA nanospheres and PLGA/ascorbic acid 85/15 wt% nanoparticles by (99m)Tc which binds outside, leaving the cage intact. This enables a quick and convenient investigation of the pharmacological behavior and metabolism of PLGA. The biodistribution of (99m)Tc-labeled PLGA particles with and without encapsulated ascorbic acid after different periods of time of their installation into rats was examined. PLGA nanospheres with encapsulated ascorbic acid exhibit prolonged blood circulation accompanied by time-dependent reduction in the lungs, liver and spleen, and addition in the kidney, stomach and intestine. The samples were characterized by x-ray diffraction, scanning electron microscopy, stereological analysis, transmission electron microscopy, ultraviolet spectroscopy and instant thin layer chromatography.",
publisher = "Bristol : IOP Science",
journal = "Nanotechnology",
title = "An innovative, quick and convenient labeling method for the investigation of pharmacological behavior and the metabolism of poly(DL-lactide-co-glycolide) nanospheres",
volume = "20",
number = "33",
doi = "10.1088/0957-4484/20/33/335102"
}
21
21
23