TY  - CONF
AU  - Marković, Bojana
AU  - Stefanović, Ivan
AU  - Popović, Aleksandar R.
AU  - Ignjatović, Nenad
AU  - Nastasović, Aleksandra
PY  - 2019
UR  - http://dais.sanu.ac.rs/123456789/7007
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/3325
AB  - Recent advances in material technologies have resulted in the preparation of novel polymer/clay composites with improved thermal, mechanical, optoelectronic/ magnetic properties and increased biodegradability [1]. In this study, six samples of poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) (PGME) nanocomposites with organically-modified montmorillonite clay Cloisite 30B® (C30B), were prepared via suspension copolymerization. In order to obtain nanocomposites with fine spherical beads of regular shape and satisfying thermal stability the optimization of the synthesis conditions was performed. Firstly, the influence of the poly(N-vinyl pyrrolidone) (PVP) quantity in the aqueous phase was varied (1, 3 and 5 wt.%) at a constant stirring rate of 250 rpm and constant clay content C30B (10 wt.%). In the second phase of the optimization of the preparation, samples with a constant composition of the composite reaction mixture (5 wt.% PVP and 10 wt.% C30B) at a stirring rate of 250, 325 and 400 rpm, were prepared. According to the obtained results, it was concluded that the optimal conditions for preparation of these composites are 5 wt.% of PVP and 400 rpm. The prepared nanocomposites were characterized with Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) in air. The structure of the prepared nanocomposites was confirmed with FTIR spectroscopy. According to the obtained SEM microphotographs the fine spherical beads, with desired size and homogeneous morphology, were prepared. Furthermore, SEM analysis was also showed that clay nanoparticles are homogeneously dispersed both inside surface and cross-section area. The incorporation of C30B clay increased the thermal stability of the prepared polymer/clay nanocomposites in comparison to the pure PGME copolymer.
PB  - Belgrade : Institute for Multidisciplinary Research
C3  - Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia
T1  - Optimization of the preparation of novel polymer/clay nanocomposites
SP  - 114
EP  - 114
UR  - https://hdl.handle.net/21.15107/rcub_dais_7007
ER  - 

@conference{
author = "Marković, Bojana and Stefanović, Ivan and Popović, Aleksandar R. and Ignjatović, Nenad and Nastasović, Aleksandra",
year = "2019",
abstract = "Recent advances in material technologies have resulted in the preparation of novel polymer/clay composites with improved thermal, mechanical, optoelectronic/ magnetic properties and increased biodegradability [1]. In this study, six samples of poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) (PGME) nanocomposites with organically-modified montmorillonite clay Cloisite 30B® (C30B), were prepared via suspension copolymerization. In order to obtain nanocomposites with fine spherical beads of regular shape and satisfying thermal stability the optimization of the synthesis conditions was performed. Firstly, the influence of the poly(N-vinyl pyrrolidone) (PVP) quantity in the aqueous phase was varied (1, 3 and 5 wt.%) at a constant stirring rate of 250 rpm and constant clay content C30B (10 wt.%). In the second phase of the optimization of the preparation, samples with a constant composition of the composite reaction mixture (5 wt.% PVP and 10 wt.% C30B) at a stirring rate of 250, 325 and 400 rpm, were prepared. According to the obtained results, it was concluded that the optimal conditions for preparation of these composites are 5 wt.% of PVP and 400 rpm. The prepared nanocomposites were characterized with Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA) in air. The structure of the prepared nanocomposites was confirmed with FTIR spectroscopy. According to the obtained SEM microphotographs the fine spherical beads, with desired size and homogeneous morphology, were prepared. Furthermore, SEM analysis was also showed that clay nanoparticles are homogeneously dispersed both inside surface and cross-section area. The incorporation of C30B clay increased the thermal stability of the prepared polymer/clay nanocomposites in comparison to the pure PGME copolymer.",
publisher = "Belgrade : Institute for Multidisciplinary Research",
journal = "Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia",
title = "Optimization of the preparation of novel polymer/clay nanocomposites",
pages = "114-114",
url = "https://hdl.handle.net/21.15107/rcub_dais_7007"
}

Marković, B., Stefanović, I., Popović, A. R., Ignjatović, N.,& Nastasović, A.. (2019). Optimization of the preparation of novel polymer/clay nanocomposites. in Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia
Belgrade : Institute for Multidisciplinary Research., 114-114.
https://hdl.handle.net/21.15107/rcub_dais_7007

Marković B, Stefanović I, Popović AR, Ignjatović N, Nastasović A. Optimization of the preparation of novel polymer/clay nanocomposites. in Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia. 2019;:114-114.
https://hdl.handle.net/21.15107/rcub_dais_7007 .

Marković, Bojana, Stefanović, Ivan, Popović, Aleksandar R., Ignjatović, Nenad, Nastasović, Aleksandra, "Optimization of the preparation of novel polymer/clay nanocomposites" in Programme and the Book of Abstracts / 5th Conference of The Serbian Society for Ceramic Materials, 5CSCS-2019, June 11-13, 2019, Belgrade, Serbia (2019):114-114,
https://hdl.handle.net/21.15107/rcub_dais_7007 .

TY  - JOUR
AU  - Jugović, Dragana
AU  - Mitrić, Miodrag
AU  - Milović, Miloš
AU  - Ivanovski, Valentin N.
AU  - Škapin, Srečo Davor
AU  - Dojčinović, Biljana
AU  - Uskoković, Dragan
PY  - 2019
UR  - http://dais.sanu.ac.rs/123456789/4938
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/3330
AB  - A new method involving the homogeneous dispersion of precursor compounds inside a methylcellulose matrix is used for the synthesis of a composite powder of Li 2 FeP 2 O 7 and carbon. The properties of carbon-containing and carbon-free powders are studied by X-ray powder diffraction (XRD) including Rietveld refinement, Mössbauer spectroscopy, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), galvanostatic cycling, and electrochemical impedance spectroscopy (EIS). The structure of both powders is refined in a monoclinic framework (space group P2 1 /c). The structural refinement and Mössbauer spectroscopy reveal different degrees of partial occupancy of mixed-occupied sites by lithium. Electrochemical measurements show that the in situ formation of carbon improves capacity (90% of 1-electron theoretical capacity) through decreased charge-transfer resistance. © 2019 Elsevier B.V.
PB  - Elsevier
T2  - Journal of Alloys and Compounds
T1  - Structural and electrochemical properties of the Li2FeP2O7/C composite prepared using soluble methylcellulose
VL  - 786
SP  - 912
EP  - 919
DO  - 10.1016/j.jallcom.2019.01.392
ER  - 

@article{
author = "Jugović, Dragana and Mitrić, Miodrag and Milović, Miloš and Ivanovski, Valentin N. and Škapin, Srečo Davor and Dojčinović, Biljana and Uskoković, Dragan",
year = "2019",
abstract = "A new method involving the homogeneous dispersion of precursor compounds inside a methylcellulose matrix is used for the synthesis of a composite powder of Li 2 FeP 2 O 7 and carbon. The properties of carbon-containing and carbon-free powders are studied by X-ray powder diffraction (XRD) including Rietveld refinement, Mössbauer spectroscopy, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), galvanostatic cycling, and electrochemical impedance spectroscopy (EIS). The structure of both powders is refined in a monoclinic framework (space group P2 1 /c). The structural refinement and Mössbauer spectroscopy reveal different degrees of partial occupancy of mixed-occupied sites by lithium. Electrochemical measurements show that the in situ formation of carbon improves capacity (90% of 1-electron theoretical capacity) through decreased charge-transfer resistance. © 2019 Elsevier B.V.",
publisher = "Elsevier",
journal = "Journal of Alloys and Compounds",
title = "Structural and electrochemical properties of the Li2FeP2O7/C composite prepared using soluble methylcellulose",
volume = "786",
pages = "912-919",
doi = "10.1016/j.jallcom.2019.01.392"
}

Jugović, D., Mitrić, M., Milović, M., Ivanovski, V. N., Škapin, S. D., Dojčinović, B.,& Uskoković, D.. (2019). Structural and electrochemical properties of the Li2FeP2O7/C composite prepared using soluble methylcellulose. in Journal of Alloys and Compounds
Elsevier., 786, 912-919.
https://doi.org/10.1016/j.jallcom.2019.01.392

Jugović D, Mitrić M, Milović M, Ivanovski VN, Škapin SD, Dojčinović B, Uskoković D. Structural and electrochemical properties of the Li2FeP2O7/C composite prepared using soluble methylcellulose. in Journal of Alloys and Compounds. 2019;786:912-919.
doi:10.1016/j.jallcom.2019.01.392 .

Jugović, Dragana, Mitrić, Miodrag, Milović, Miloš, Ivanovski, Valentin N., Škapin, Srečo Davor, Dojčinović, Biljana, Uskoković, Dragan, "Structural and electrochemical properties of the Li2FeP2O7/C composite prepared using soluble methylcellulose" in Journal of Alloys and Compounds, 786 (2019):912-919,
https://doi.org/10.1016/j.jallcom.2019.01.392 . .

TY  - JOUR
AU  - Jugović, Dragana
AU  - Mitrić, Miodrag
AU  - Milović, Miloš
AU  - Ivanovski, Valentin N.
AU  - Škapin, Srečo Davor
AU  - Dojčinović, Biljana
AU  - Uskoković, Dragan
PY  - 2019
UR  - http://dais.sanu.ac.rs/123456789/4937
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/2649
AB  - A new method involving the homogeneous dispersion of precursor compounds inside a methylcellulose matrix is used for the synthesis of a composite powder of Li 2 FeP 2 O 7 and carbon. The properties of carbon-containing and carbon-free powders are studied by X-ray powder diffraction (XRD) including Rietveld refinement, Mössbauer spectroscopy, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), galvanostatic cycling, and electrochemical impedance spectroscopy (EIS). The structure of both powders is refined in a monoclinic framework (space group P2 1 /c). The structural refinement and Mössbauer spectroscopy reveal different degrees of partial occupancy of mixed-occupied sites by lithium. Electrochemical measurements show that the in situ formation of carbon improves capacity (90% of 1-electron theoretical capacity) through decreased charge-transfer resistance. © 2019 Elsevier B.V.
PB  - Elsevier
T2  - Journal of Alloys and Compounds
T1  - Structural and electrochemical properties of the Li2FeP2O7/C composite prepared using soluble methylcellulose
VL  - 786
SP  - 912
EP  - 919
DO  - 10.1016/j.jallcom.2019.01.392
ER  - 

@article{
author = "Jugović, Dragana and Mitrić, Miodrag and Milović, Miloš and Ivanovski, Valentin N. and Škapin, Srečo Davor and Dojčinović, Biljana and Uskoković, Dragan",
year = "2019",
abstract = "A new method involving the homogeneous dispersion of precursor compounds inside a methylcellulose matrix is used for the synthesis of a composite powder of Li 2 FeP 2 O 7 and carbon. The properties of carbon-containing and carbon-free powders are studied by X-ray powder diffraction (XRD) including Rietveld refinement, Mössbauer spectroscopy, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), galvanostatic cycling, and electrochemical impedance spectroscopy (EIS). The structure of both powders is refined in a monoclinic framework (space group P2 1 /c). The structural refinement and Mössbauer spectroscopy reveal different degrees of partial occupancy of mixed-occupied sites by lithium. Electrochemical measurements show that the in situ formation of carbon improves capacity (90% of 1-electron theoretical capacity) through decreased charge-transfer resistance. © 2019 Elsevier B.V.",
publisher = "Elsevier",
journal = "Journal of Alloys and Compounds",
title = "Structural and electrochemical properties of the Li2FeP2O7/C composite prepared using soluble methylcellulose",
volume = "786",
pages = "912-919",
doi = "10.1016/j.jallcom.2019.01.392"
}

Jugović, D., Mitrić, M., Milović, M., Ivanovski, V. N., Škapin, S. D., Dojčinović, B.,& Uskoković, D.. (2019). Structural and electrochemical properties of the Li2FeP2O7/C composite prepared using soluble methylcellulose. in Journal of Alloys and Compounds
Elsevier., 786, 912-919.
https://doi.org/10.1016/j.jallcom.2019.01.392

Jugović D, Mitrić M, Milović M, Ivanovski VN, Škapin SD, Dojčinović B, Uskoković D. Structural and electrochemical properties of the Li2FeP2O7/C composite prepared using soluble methylcellulose. in Journal of Alloys and Compounds. 2019;786:912-919.
doi:10.1016/j.jallcom.2019.01.392 .

Jugović, Dragana, Mitrić, Miodrag, Milović, Miloš, Ivanovski, Valentin N., Škapin, Srečo Davor, Dojčinović, Biljana, Uskoković, Dragan, "Structural and electrochemical properties of the Li2FeP2O7/C composite prepared using soluble methylcellulose" in Journal of Alloys and Compounds, 786 (2019):912-919,
https://doi.org/10.1016/j.jallcom.2019.01.392 . .

TY  - JOUR
AU  - Ignjatović, Nenad
AU  - Sakač, Marija
AU  - Kuzminac, Ivana
AU  - Kojić, Vesna V.
AU  - Marković, Smilja B.
AU  - Vasiljević-Radović, Dana
AU  - Wu, Victoria
AU  - Uskoković, Vuk
AU  - Uskoković, Dragan
PY  - 2018
UR  - http://dais.sanu.ac.rs/123456789/4066
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/3146
AB  - Low targeting efficiency and fast metabolism of antineoplastic drugs are hindrances to effective chemotherapies and there is an ongoing search for better drugs, but also better carriers. Steroid derivatives, 3β-hydroxy-16-hydroxymino-androst-5-en-17-one (A) and 3β,17β-dihydroxy-16-hydroxymino-androst-5-ene (B) as cancer growth inhibitors were chemically synthesized and captured in a carrier composed of hydroxyapatite (HAp) nanoparticles coated with chitosan oligosaccharide lactate (ChOLS). The only difference between the two derivatives is that A has a carbonyl group at the C17 position of the five-membered ring and B has a hydroxyl. This small difference in the structure resulted not only in different physicochemical properties of the A- and B-loaded HAp/ChOSL, but also in different biological activities. The morphology of drug-loaded HAp/ChOSL particles was spherical, but the size depended on the drug identity: d50 = 138 nm for A-loaded HAp/ChOSL and d50 = 223 nm for B-loaded HAp/ChOSL. Cell-selective toxicity was tested against human breast carcinoma (MCF7 and MDA-MB-231), human lung carcinoma (A549) and human lung fibroblasts (MRC-5). The small selectivity of pure derivatives A and B toward breast cancer cells became drastically increased when they were delivered using HAp/ChOSL particles. Whereas the ratio of the cytotoxicity imposed onto breast cancer cells and the cytotoxicity imposed onto healthy MRC-5 fibroblasts ranged from 1.5 to 1.7 for pure A and from 1.5 to 2.3 for pure derivative B depending on the concentration, it increased to 5.4 for A-loaded HAp/ChOSL and 5.1 for B-loaded HAp/ChOSL. FACS analysis demonstrated poor uptake of HAp/ChOSL particles by MCF7 cells, suggesting that the drug release occurs extracellularly. The augmented activity of the drugs was most likely due to sustained release, although the favorable positive charge of the carrier, allowing it to adhere to the negatively charged plasma membrane and release the drugs steadily and directly to the hydrophobic cell membrane milieu, was delineated as a possible complementary mechanism.
PB  - Royal Society of Chemistry
T2  - Journal of Materials Chemistry B
T1  - Chitosan oligosaccharide lactate coated hydroxyapatite nanoparticles as a vehicle for the delivery of steroid drugs and the targeting of breast cancer cells
VL  - 6
SP  - 6957
EP  - 6968
DO  - 10.1039/C8TB01995A
ER  - 

@article{
author = "Ignjatović, Nenad and Sakač, Marija and Kuzminac, Ivana and Kojić, Vesna V. and Marković, Smilja B. and Vasiljević-Radović, Dana and Wu, Victoria and Uskoković, Vuk and Uskoković, Dragan",
year = "2018",
abstract = "Low targeting efficiency and fast metabolism of antineoplastic drugs are hindrances to effective chemotherapies and there is an ongoing search for better drugs, but also better carriers. Steroid derivatives, 3β-hydroxy-16-hydroxymino-androst-5-en-17-one (A) and 3β,17β-dihydroxy-16-hydroxymino-androst-5-ene (B) as cancer growth inhibitors were chemically synthesized and captured in a carrier composed of hydroxyapatite (HAp) nanoparticles coated with chitosan oligosaccharide lactate (ChOLS). The only difference between the two derivatives is that A has a carbonyl group at the C17 position of the five-membered ring and B has a hydroxyl. This small difference in the structure resulted not only in different physicochemical properties of the A- and B-loaded HAp/ChOSL, but also in different biological activities. The morphology of drug-loaded HAp/ChOSL particles was spherical, but the size depended on the drug identity: d50 = 138 nm for A-loaded HAp/ChOSL and d50 = 223 nm for B-loaded HAp/ChOSL. Cell-selective toxicity was tested against human breast carcinoma (MCF7 and MDA-MB-231), human lung carcinoma (A549) and human lung fibroblasts (MRC-5). The small selectivity of pure derivatives A and B toward breast cancer cells became drastically increased when they were delivered using HAp/ChOSL particles. Whereas the ratio of the cytotoxicity imposed onto breast cancer cells and the cytotoxicity imposed onto healthy MRC-5 fibroblasts ranged from 1.5 to 1.7 for pure A and from 1.5 to 2.3 for pure derivative B depending on the concentration, it increased to 5.4 for A-loaded HAp/ChOSL and 5.1 for B-loaded HAp/ChOSL. FACS analysis demonstrated poor uptake of HAp/ChOSL particles by MCF7 cells, suggesting that the drug release occurs extracellularly. The augmented activity of the drugs was most likely due to sustained release, although the favorable positive charge of the carrier, allowing it to adhere to the negatively charged plasma membrane and release the drugs steadily and directly to the hydrophobic cell membrane milieu, was delineated as a possible complementary mechanism.",
publisher = "Royal Society of Chemistry",
journal = "Journal of Materials Chemistry B",
title = "Chitosan oligosaccharide lactate coated hydroxyapatite nanoparticles as a vehicle for the delivery of steroid drugs and the targeting of breast cancer cells",
volume = "6",
pages = "6957-6968",
doi = "10.1039/C8TB01995A"
}

Ignjatović, N., Sakač, M., Kuzminac, I., Kojić, V. V., Marković, S. B., Vasiljević-Radović, D., Wu, V., Uskoković, V.,& Uskoković, D.. (2018). Chitosan oligosaccharide lactate coated hydroxyapatite nanoparticles as a vehicle for the delivery of steroid drugs and the targeting of breast cancer cells. in Journal of Materials Chemistry B
Royal Society of Chemistry., 6, 6957-6968.
https://doi.org/10.1039/C8TB01995A

Ignjatović N, Sakač M, Kuzminac I, Kojić VV, Marković SB, Vasiljević-Radović D, Wu V, Uskoković V, Uskoković D. Chitosan oligosaccharide lactate coated hydroxyapatite nanoparticles as a vehicle for the delivery of steroid drugs and the targeting of breast cancer cells. in Journal of Materials Chemistry B. 2018;6:6957-6968.
doi:10.1039/C8TB01995A .

Ignjatović, Nenad, Sakač, Marija, Kuzminac, Ivana, Kojić, Vesna V., Marković, Smilja B., Vasiljević-Radović, Dana, Wu, Victoria, Uskoković, Vuk, Uskoković, Dragan, "Chitosan oligosaccharide lactate coated hydroxyapatite nanoparticles as a vehicle for the delivery of steroid drugs and the targeting of breast cancer cells" in Journal of Materials Chemistry B, 6 (2018):6957-6968,
https://doi.org/10.1039/C8TB01995A . .

TY  - JOUR
AU  - Ignjatović, Nenad
AU  - Sakač, Marija
AU  - Kuzminac, Ivana
AU  - Kojić, Vesna V.
AU  - Marković, Smilja B.
AU  - Vasiljević-Radović, Dana
AU  - Wu, Victoria M.
AU  - Uskoković, Vuk
AU  - Uskoković, Dragan P.
PY  - 2018
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/2482
AB  - Low targeting efficiency and fast metabolism of antineoplastic drugs are hindrances to effective chemotherapies and there is an ongoing search for better drugs, but also better carriers. Steroid derivatives, 3-hydroxy-16-hydroxymino-androst-5-en-17-one (A) and 3,17-dihydroxy-16-hydroxymino-androst-5-ene (B) as cancer growth inhibitors were chemically synthesized and captured in a carrier composed of hydroxyapatite (HAp) nanoparticles coated with chitosan oligosaccharide lactate (ChOLS). The only difference between the two derivatives is that A has a carbonyl group at the C17 position of the five-membered ring and B has a hydroxyl. This small difference in the structure resulted not only in different physicochemical properties of the A- and B-loaded HAp/ChOSL, but also in different biological activities. The morphology of drug-loaded HAp/ChOSL particles was spherical, but the size depended on the drug identity: d(50) = 138 nm for A-loaded HAp/ChOSL and d(50) = 223 nm for B-loaded HAp/ChOSL. Cell-selective toxicity was tested against human breast carcinoma (MCF7 and MDA-MB-231), human lung carcinoma (A549) and human lung fibroblasts (MRC-5). The small selectivity of pure derivatives A and B toward breast cancer cells became drastically increased when they were delivered using HAp/ChOSL particles. Whereas the ratio of the cytotoxicity imposed onto breast cancer cells and the cytotoxicity imposed onto healthy MRC-5 fibroblasts ranged from 1.5 to 1.7 for pure A and from 1.5 to 2.3 for pure derivative B depending on the concentration, it increased to 5.4 for A-loaded HAp/ChOSL and 5.1 for B-loaded HAp/ChOSL. FACS analysis demonstrated poor uptake of HAp/ChOSL particles by MCF7 cells, suggesting that the drug release occurs extracellularly. The augmented activity of the drugs was most likely due to sustained release, although the favorable positive charge of the carrier, allowing it to adhere to the negatively charged plasma membrane and release the drugs steadily and directly to the hydrophobic cell membrane milieu, was delineated as a possible complementary mechanism.
PB  - Royal Society of Chemistry
T2  - Journal of Materials Chemistry B
T1  - Chitosan oligosaccharide lactate coated hydroxyapatite nanoparticles as a vehicle for the delivery of steroid drugs and the targeting of breast cancer cells
VL  - 6
IS  - 43
SP  - 6957
EP  - 6968
DO  - 10.1039/c8tb01995a
ER  - 

@article{
author = "Ignjatović, Nenad and Sakač, Marija and Kuzminac, Ivana and Kojić, Vesna V. and Marković, Smilja B. and Vasiljević-Radović, Dana and Wu, Victoria M. and Uskoković, Vuk and Uskoković, Dragan P.",
year = "2018",
abstract = "Low targeting efficiency and fast metabolism of antineoplastic drugs are hindrances to effective chemotherapies and there is an ongoing search for better drugs, but also better carriers. Steroid derivatives, 3-hydroxy-16-hydroxymino-androst-5-en-17-one (A) and 3,17-dihydroxy-16-hydroxymino-androst-5-ene (B) as cancer growth inhibitors were chemically synthesized and captured in a carrier composed of hydroxyapatite (HAp) nanoparticles coated with chitosan oligosaccharide lactate (ChOLS). The only difference between the two derivatives is that A has a carbonyl group at the C17 position of the five-membered ring and B has a hydroxyl. This small difference in the structure resulted not only in different physicochemical properties of the A- and B-loaded HAp/ChOSL, but also in different biological activities. The morphology of drug-loaded HAp/ChOSL particles was spherical, but the size depended on the drug identity: d(50) = 138 nm for A-loaded HAp/ChOSL and d(50) = 223 nm for B-loaded HAp/ChOSL. Cell-selective toxicity was tested against human breast carcinoma (MCF7 and MDA-MB-231), human lung carcinoma (A549) and human lung fibroblasts (MRC-5). The small selectivity of pure derivatives A and B toward breast cancer cells became drastically increased when they were delivered using HAp/ChOSL particles. Whereas the ratio of the cytotoxicity imposed onto breast cancer cells and the cytotoxicity imposed onto healthy MRC-5 fibroblasts ranged from 1.5 to 1.7 for pure A and from 1.5 to 2.3 for pure derivative B depending on the concentration, it increased to 5.4 for A-loaded HAp/ChOSL and 5.1 for B-loaded HAp/ChOSL. FACS analysis demonstrated poor uptake of HAp/ChOSL particles by MCF7 cells, suggesting that the drug release occurs extracellularly. The augmented activity of the drugs was most likely due to sustained release, although the favorable positive charge of the carrier, allowing it to adhere to the negatively charged plasma membrane and release the drugs steadily and directly to the hydrophobic cell membrane milieu, was delineated as a possible complementary mechanism.",
publisher = "Royal Society of Chemistry",
journal = "Journal of Materials Chemistry B",
title = "Chitosan oligosaccharide lactate coated hydroxyapatite nanoparticles as a vehicle for the delivery of steroid drugs and the targeting of breast cancer cells",
volume = "6",
number = "43",
pages = "6957-6968",
doi = "10.1039/c8tb01995a"
}

Ignjatović, N., Sakač, M., Kuzminac, I., Kojić, V. V., Marković, S. B., Vasiljević-Radović, D., Wu, V. M., Uskoković, V.,& Uskoković, D. P.. (2018). Chitosan oligosaccharide lactate coated hydroxyapatite nanoparticles as a vehicle for the delivery of steroid drugs and the targeting of breast cancer cells. in Journal of Materials Chemistry B
Royal Society of Chemistry., 6(43), 6957-6968.
https://doi.org/10.1039/c8tb01995a

Ignjatović N, Sakač M, Kuzminac I, Kojić VV, Marković SB, Vasiljević-Radović D, Wu VM, Uskoković V, Uskoković DP. Chitosan oligosaccharide lactate coated hydroxyapatite nanoparticles as a vehicle for the delivery of steroid drugs and the targeting of breast cancer cells. in Journal of Materials Chemistry B. 2018;6(43):6957-6968.
doi:10.1039/c8tb01995a .

Ignjatović, Nenad, Sakač, Marija, Kuzminac, Ivana, Kojić, Vesna V., Marković, Smilja B., Vasiljević-Radović, Dana, Wu, Victoria M., Uskoković, Vuk, Uskoković, Dragan P., "Chitosan oligosaccharide lactate coated hydroxyapatite nanoparticles as a vehicle for the delivery of steroid drugs and the targeting of breast cancer cells" in Journal of Materials Chemistry B, 6, no. 43 (2018):6957-6968,
https://doi.org/10.1039/c8tb01995a . .

TY  - JOUR
AU  - Marković, Smilja B.
AU  - Stankovic, Ana
AU  - Dostanić, Jasmina
AU  - Veselinović, Ljiljana
AU  - Mančić, Lidija
AU  - Skapin, Sreco Davor
AU  - Drazic, Goran
AU  - Janković-Častvan, Ivona
AU  - Uskoković, Dragan P.
PY  - 2017
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/2169
AB  - Mechanical milling of commercial ZnO and SnO2 was used to produce a ZnO/SnO2 composite with a high density of surface defects; in particular, zinc interstitials (Zni) and oxygen vacancies (VO). To determine the impact of surface defects on photocatalytic activity, the relative concentration ratio of bulk defects to surface defects was modified by annealing at 400 and 700 degrees C. The possible application of the ZnO/SnO2 composite as a natural sunlight and UV- light driven photocatalyst was revealed via de-colorization of methylene blue. In both cases the ZnO/SnO2 composite exhibited enhanced photocatalytic activity as compared to the pristine ZnO. In order to investigate the origin of the enhancement, the pristine metal oxides and composites were characterized using a variety of techniques, including X-ray diffraction (XRD), Raman and Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), laser diffraction particle size analysis, Brunauer-Emmett-Teller, UV-Vis diffuse reflectance and photoluminescence spectroscopy. High-resolution transmission electron microscopy (HRTEM) and elemental mapping analyses were used to reveal the presence of SnO2 nanocrystallites on the surface of larger ZnO particles. The enhanced photocatalytic activity of the composite can be attributed to the synergetic effect of the surface defects and the ZnO/SnO2 heterojunction particles, which facilitated charge separation, thereby hindering the recombination of photogenerated carriers. This study draws attention to mechanical activation as an inexpensive and environmentally friendly technique for the large-scale production of the composite with an enhanced photocatalytic activity under illumination of either UV or sunlight.
PB  - The Royal Society of Chemistry
T2  - RSC Advances
T1  - Simultaneous enhancement of natural sunlightand artificial UV-driven photocatalytic activity of a mechanically activated ZnO/SnO2 composite
VL  - 7
IS  - 68
SP  - 42725
EP  - 42737
DO  - 10.1039/c7ra06895f
ER  - 

@article{
author = "Marković, Smilja B. and Stankovic, Ana and Dostanić, Jasmina and Veselinović, Ljiljana and Mančić, Lidija and Skapin, Sreco Davor and Drazic, Goran and Janković-Častvan, Ivona and Uskoković, Dragan P.",
year = "2017",
abstract = "Mechanical milling of commercial ZnO and SnO2 was used to produce a ZnO/SnO2 composite with a high density of surface defects; in particular, zinc interstitials (Zni) and oxygen vacancies (VO). To determine the impact of surface defects on photocatalytic activity, the relative concentration ratio of bulk defects to surface defects was modified by annealing at 400 and 700 degrees C. The possible application of the ZnO/SnO2 composite as a natural sunlight and UV- light driven photocatalyst was revealed via de-colorization of methylene blue. In both cases the ZnO/SnO2 composite exhibited enhanced photocatalytic activity as compared to the pristine ZnO. In order to investigate the origin of the enhancement, the pristine metal oxides and composites were characterized using a variety of techniques, including X-ray diffraction (XRD), Raman and Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), laser diffraction particle size analysis, Brunauer-Emmett-Teller, UV-Vis diffuse reflectance and photoluminescence spectroscopy. High-resolution transmission electron microscopy (HRTEM) and elemental mapping analyses were used to reveal the presence of SnO2 nanocrystallites on the surface of larger ZnO particles. The enhanced photocatalytic activity of the composite can be attributed to the synergetic effect of the surface defects and the ZnO/SnO2 heterojunction particles, which facilitated charge separation, thereby hindering the recombination of photogenerated carriers. This study draws attention to mechanical activation as an inexpensive and environmentally friendly technique for the large-scale production of the composite with an enhanced photocatalytic activity under illumination of either UV or sunlight.",
publisher = "The Royal Society of Chemistry",
journal = "RSC Advances",
title = "Simultaneous enhancement of natural sunlightand artificial UV-driven photocatalytic activity of a mechanically activated ZnO/SnO2 composite",
volume = "7",
number = "68",
pages = "42725-42737",
doi = "10.1039/c7ra06895f"
}

Marković, S. B., Stankovic, A., Dostanić, J., Veselinović, L., Mančić, L., Skapin, S. D., Drazic, G., Janković-Častvan, I.,& Uskoković, D. P.. (2017). Simultaneous enhancement of natural sunlightand artificial UV-driven photocatalytic activity of a mechanically activated ZnO/SnO2 composite. in RSC Advances
The Royal Society of Chemistry., 7(68), 42725-42737.
https://doi.org/10.1039/c7ra06895f

Marković SB, Stankovic A, Dostanić J, Veselinović L, Mančić L, Skapin SD, Drazic G, Janković-Častvan I, Uskoković DP. Simultaneous enhancement of natural sunlightand artificial UV-driven photocatalytic activity of a mechanically activated ZnO/SnO2 composite. in RSC Advances. 2017;7(68):42725-42737.
doi:10.1039/c7ra06895f .

Marković, Smilja B., Stankovic, Ana, Dostanić, Jasmina, Veselinović, Ljiljana, Mančić, Lidija, Skapin, Sreco Davor, Drazic, Goran, Janković-Častvan, Ivona, Uskoković, Dragan P., "Simultaneous enhancement of natural sunlightand artificial UV-driven photocatalytic activity of a mechanically activated ZnO/SnO2 composite" in RSC Advances, 7, no. 68 (2017):42725-42737,
https://doi.org/10.1039/c7ra06895f . .

TY  - CONF
AU  - Marković, Smilja B.
AU  - Stanković, Ana
AU  - Dostanić, Jasmina
AU  - Mančić, Lidija
AU  - Škapin, Srečo Davor
AU  - Uskoković, Dragan
PY  - 2017
UR  - http://dais.sanu.ac.rs/123456789/15440
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/2866
AB  - Over the past four decades there is an increasing interest to develop highly efficient semiconductor photocatalysts for degradation of organic and biological pollutants in water under light irradiation. The semiconductor band gap determines which wavelength of light will be absorbed; precisely, semiconductors with a wide band gap (> 3 eV) can absorb only UV light, while those with a narrow band gap (< 3 eV) can be activated by visible light.In this study we examined structural, morphological, textural and optical properties of ZnO/SnO2 composite as potential photocatalyst. Mechanical activation of commercial ZnO and SnO2 powders has been used to produce a composite with high density of surface defects. To investigate the influence of thermal treatment on the physical properties, and consequently on photoactivity, the composite has been traditionally annealed at 400 and 700 °C. The phase purity, crystal structure and average crystallite size of pristine metal oxides and the composites were investigated by X-ray diffraction and Raman spectroscopy. The particles morphology and size distributions were studied by FE–SEM and laser diffraction particle size analyzer, respectively. The textural properties were determined from N¬2¬ adsorption/desorption experiments, while the optical properties were studied using UV–Vis diffuse reflectance and photoluminescence spectroscopy. Photocatalytic activity of pristine ZnO and ZnO/SnO2 composites were examined via de-colorization of methylene blue under: (1) direct natural sunlight, and (2) artificial UV irradiation. In both cases enhanced photocatalytic activity of ZnO/SnO2 has been found. Enhanced photocatalytic activity can be attributed to the surface defects and to created ZnO/SnO2 heterojunctions which reduced electron-hole recombination time.
PB  - Belgrade : Materials Research Society of Serbia
C3  - Programme and The Book of Abstracts / Nineteenth Annual Conference YUCOMAT 2017, Herceg Novi, September 4-8, 2017
T1  - Enhanced natural sunlight- and artificial UV-driven photocatalytic activity of mechanically activated ZnO/SnO2 composite
SP  - 49
EP  - 49
UR  - https://hdl.handle.net/21.15107/rcub_dais_15440
ER  - 

@conference{
author = "Marković, Smilja B. and Stanković, Ana and Dostanić, Jasmina and Mančić, Lidija and Škapin, Srečo Davor and Uskoković, Dragan",
year = "2017",
abstract = "Over the past four decades there is an increasing interest to develop highly efficient semiconductor photocatalysts for degradation of organic and biological pollutants in water under light irradiation. The semiconductor band gap determines which wavelength of light will be absorbed; precisely, semiconductors with a wide band gap (> 3 eV) can absorb only UV light, while those with a narrow band gap (< 3 eV) can be activated by visible light.In this study we examined structural, morphological, textural and optical properties of ZnO/SnO2 composite as potential photocatalyst. Mechanical activation of commercial ZnO and SnO2 powders has been used to produce a composite with high density of surface defects. To investigate the influence of thermal treatment on the physical properties, and consequently on photoactivity, the composite has been traditionally annealed at 400 and 700 °C. The phase purity, crystal structure and average crystallite size of pristine metal oxides and the composites were investigated by X-ray diffraction and Raman spectroscopy. The particles morphology and size distributions were studied by FE–SEM and laser diffraction particle size analyzer, respectively. The textural properties were determined from N¬2¬ adsorption/desorption experiments, while the optical properties were studied using UV–Vis diffuse reflectance and photoluminescence spectroscopy. Photocatalytic activity of pristine ZnO and ZnO/SnO2 composites were examined via de-colorization of methylene blue under: (1) direct natural sunlight, and (2) artificial UV irradiation. In both cases enhanced photocatalytic activity of ZnO/SnO2 has been found. Enhanced photocatalytic activity can be attributed to the surface defects and to created ZnO/SnO2 heterojunctions which reduced electron-hole recombination time.",
publisher = "Belgrade : Materials Research Society of Serbia",
journal = "Programme and The Book of Abstracts / Nineteenth Annual Conference YUCOMAT 2017, Herceg Novi, September 4-8, 2017",
title = "Enhanced natural sunlight- and artificial UV-driven photocatalytic activity of mechanically activated ZnO/SnO2 composite",
pages = "49-49",
url = "https://hdl.handle.net/21.15107/rcub_dais_15440"
}

Marković, S. B., Stanković, A., Dostanić, J., Mančić, L., Škapin, S. D.,& Uskoković, D.. (2017). Enhanced natural sunlight- and artificial UV-driven photocatalytic activity of mechanically activated ZnO/SnO2 composite. in Programme and The Book of Abstracts / Nineteenth Annual Conference YUCOMAT 2017, Herceg Novi, September 4-8, 2017
Belgrade : Materials Research Society of Serbia., 49-49.
https://hdl.handle.net/21.15107/rcub_dais_15440

Marković SB, Stanković A, Dostanić J, Mančić L, Škapin SD, Uskoković D. Enhanced natural sunlight- and artificial UV-driven photocatalytic activity of mechanically activated ZnO/SnO2 composite. in Programme and The Book of Abstracts / Nineteenth Annual Conference YUCOMAT 2017, Herceg Novi, September 4-8, 2017. 2017;:49-49.
https://hdl.handle.net/21.15107/rcub_dais_15440 .

Marković, Smilja B., Stanković, Ana, Dostanić, Jasmina, Mančić, Lidija, Škapin, Srečo Davor, Uskoković, Dragan, "Enhanced natural sunlight- and artificial UV-driven photocatalytic activity of mechanically activated ZnO/SnO2 composite" in Programme and The Book of Abstracts / Nineteenth Annual Conference YUCOMAT 2017, Herceg Novi, September 4-8, 2017 (2017):49-49,
https://hdl.handle.net/21.15107/rcub_dais_15440 .

TY  - JOUR
AU  - Ignjatović, Nenad
AU  - Penov-Gasi, Katarina M.
AU  - Wu, Victoria M.
AU  - Ajduković, Jovana J.
AU  - Kojić, Vesna V.
AU  - Vasiljević-Radović, Dana
AU  - Kuzmanovic, Maja
AU  - Uskokovicć, Vuk
AU  - Uskoković, Dragan P.
PY  - 2016
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/1996
AB  - In an earlier study we demonstrated that hydroxyapatite nanoparticles coated with chitosan-poly(D,L)-lactide-co-glycolide (HAp/Ch-PLGA) target lungs following their intravenous injection into mice. In this study we utilize an emulsification process and freeze drying to load the composite HAp/Ch-PLGA particles with 17 beta-hydroxy-17 alpha-picolyl-androst-5-en-3 beta-yl-acetate (A), a chemotherapeutic derivative of androstane and a novel compound with a selective anticancer activity against lung cancer cells. H-1 NMR and C-13 NMR techniques confirmed the intact structure of the derivative A following its entrapment within HAp/Ch-PLGA particles. The thermogravimetric and differential thermal analyses coupled with mass spectrometry were used to assess the thermal degradation products and properties of A-loaded HAp/Ch-PLGA. The loading efficiency, as indicated by the comparison of enthalpies of phase transitions in pure A and A-loaded HAp/Ch-PLGA, equaled 7.47 wt.%. The release of A from HAp/Ch-PLGA was sustained, neither exhibiting a burst release nor plateauing after three weeks. Atomic force microscopy and particle size distribution analyses were used to confirm that the particles were spherical with a uniform size distribution of d(50) = 168 nm. In vitro cytotoxicity testing of A-loaded HAp/Ch-PLGA using MTT and trypan blue dye exclusion assays demonstrated that the particles were cytotoxic to the A549 human lung carcinoma cell line (46 +/- 2%), while simultaneously preserving high viability (83 +/- 3%) of regular MRC5 human lung fibroblasts and causing no harm to primary mouse lung fibroblasts. In conclusion, composite A-loaded HAp/Ch-PLGA particles could be seen as promising drug delivery platforms for selective cancer therapies, targeting malignant cells for destruction, while having a significantly lesser cytotoxic effect on the healthy cells.
PB  - Elsevier
T2  - Colloids and Surfaces B-Biointerfaces
T1  - Selective anticancer activity of hydroxyapatite/chitosan-poly(D,L)-lactide-co-glycolide particles loaded with an androstane-based cancer inhibitor
VL  - 148
SP  - 629
EP  - 639
DO  - 10.1016/j.colsurfb.2016.09.041
ER  - 

@article{
author = "Ignjatović, Nenad and Penov-Gasi, Katarina M. and Wu, Victoria M. and Ajduković, Jovana J. and Kojić, Vesna V. and Vasiljević-Radović, Dana and Kuzmanovic, Maja and Uskokovicć, Vuk and Uskoković, Dragan P.",
year = "2016",
abstract = "In an earlier study we demonstrated that hydroxyapatite nanoparticles coated with chitosan-poly(D,L)-lactide-co-glycolide (HAp/Ch-PLGA) target lungs following their intravenous injection into mice. In this study we utilize an emulsification process and freeze drying to load the composite HAp/Ch-PLGA particles with 17 beta-hydroxy-17 alpha-picolyl-androst-5-en-3 beta-yl-acetate (A), a chemotherapeutic derivative of androstane and a novel compound with a selective anticancer activity against lung cancer cells. H-1 NMR and C-13 NMR techniques confirmed the intact structure of the derivative A following its entrapment within HAp/Ch-PLGA particles. The thermogravimetric and differential thermal analyses coupled with mass spectrometry were used to assess the thermal degradation products and properties of A-loaded HAp/Ch-PLGA. The loading efficiency, as indicated by the comparison of enthalpies of phase transitions in pure A and A-loaded HAp/Ch-PLGA, equaled 7.47 wt.%. The release of A from HAp/Ch-PLGA was sustained, neither exhibiting a burst release nor plateauing after three weeks. Atomic force microscopy and particle size distribution analyses were used to confirm that the particles were spherical with a uniform size distribution of d(50) = 168 nm. In vitro cytotoxicity testing of A-loaded HAp/Ch-PLGA using MTT and trypan blue dye exclusion assays demonstrated that the particles were cytotoxic to the A549 human lung carcinoma cell line (46 +/- 2%), while simultaneously preserving high viability (83 +/- 3%) of regular MRC5 human lung fibroblasts and causing no harm to primary mouse lung fibroblasts. In conclusion, composite A-loaded HAp/Ch-PLGA particles could be seen as promising drug delivery platforms for selective cancer therapies, targeting malignant cells for destruction, while having a significantly lesser cytotoxic effect on the healthy cells.",
publisher = "Elsevier",
journal = "Colloids and Surfaces B-Biointerfaces",
title = "Selective anticancer activity of hydroxyapatite/chitosan-poly(D,L)-lactide-co-glycolide particles loaded with an androstane-based cancer inhibitor",
volume = "148",
pages = "629-639",
doi = "10.1016/j.colsurfb.2016.09.041"
}

Ignjatović, N., Penov-Gasi, K. M., Wu, V. M., Ajduković, J. J., Kojić, V. V., Vasiljević-Radović, D., Kuzmanovic, M., Uskokovicć, V.,& Uskoković, D. P.. (2016). Selective anticancer activity of hydroxyapatite/chitosan-poly(D,L)-lactide-co-glycolide particles loaded with an androstane-based cancer inhibitor. in Colloids and Surfaces B-Biointerfaces
Elsevier., 148, 629-639.
https://doi.org/10.1016/j.colsurfb.2016.09.041

Ignjatović N, Penov-Gasi KM, Wu VM, Ajduković JJ, Kojić VV, Vasiljević-Radović D, Kuzmanovic M, Uskokovicć V, Uskoković DP. Selective anticancer activity of hydroxyapatite/chitosan-poly(D,L)-lactide-co-glycolide particles loaded with an androstane-based cancer inhibitor. in Colloids and Surfaces B-Biointerfaces. 2016;148:629-639.
doi:10.1016/j.colsurfb.2016.09.041 .

Ignjatović, Nenad, Penov-Gasi, Katarina M., Wu, Victoria M., Ajduković, Jovana J., Kojić, Vesna V., Vasiljević-Radović, Dana, Kuzmanovic, Maja, Uskokovicć, Vuk, Uskoković, Dragan P., "Selective anticancer activity of hydroxyapatite/chitosan-poly(D,L)-lactide-co-glycolide particles loaded with an androstane-based cancer inhibitor" in Colloids and Surfaces B-Biointerfaces, 148 (2016):629-639,
https://doi.org/10.1016/j.colsurfb.2016.09.041 . .

TY  - JOUR
AU  - Ignjatović, Nenad
AU  - Penov Gaši, Katarina
AU  - Wu, Victoria
AU  - Ajduković, Jovana
AU  - Kojić, Vesna V.
AU  - Vasiljević-Radović, Dana
AU  - Kuzmanović, Maja
AU  - Uskoković, Vuk
AU  - Uskoković, Dragan P.
PY  - 2016
UR  - http://dais.sanu.ac.rs/123456789/15984
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/2644
AB  - In an earlier study we demonstrated that hydroxyapatite nanoparticles coated with chitosan-poly(d,l)-lactide-co-glycolide (HAp/Ch-PLGA) target lungs following their intravenous injection into mice. In this study we utilize an emulsification process and freeze drying to load the composite HAp/Ch-PLGA particles with 17β-hydroxy-17α-picolyl-androst-5-en-3β-yl-acetate (A), a chemotherapeutic derivative of androstane and a novel compound with a selective anticancer activity against lung cancer cells. 1H NMR and 13C NMR techniques confirmed the intact structure of the derivative A following its entrapment within HAp/Ch-PLGA particles. The thermogravimetric and differential thermal analyses coupled with mass spectrometry were used to assess the thermal degradation products and properties of A-loaded HAp/Ch-PLGA. The loading efficiency, as indicated by the comparison of enthalpies of phase transitions in pure A and A-loaded HAp/Ch-PLGA, equaled 7.47 wt.%. The release of A from HAp/Ch-PLGA was sustained, neither exhibiting a burst release nor plateauing after three weeks. Atomic force microscopy and particle size distribution analyses were used to confirm that the particles were spherical with a uniform size distribution of d50 = 168 nm. In vitro cytotoxicity testing of A-loaded HAp/Ch-PLGA using MTT and trypan blue dye exclusion assays demonstrated that the particles were cytotoxic to the A549 human lung carcinoma cell line (46 ± 2%), while simultaneously preserving high viability (83 ± 3%) of regular MRC5 human lung fibroblasts and causing no harm to primary mouse lung fibroblasts. In conclusion, composite A-loaded HAp/Ch-PLGA particles could be seen as promising drug delivery platforms for selective cancer therapies, targeting malignant cells for destruction, while having a significantly lesser cytotoxic effect on the healthy cells.
T2  - Colloids and Surfaces B: Biointerfaces
T1  - Selective anticancer activity of hydroxyapatite/chitosan-poly(D,L)-lactide-co-glycolide particles loaded with an androstane-based cancer inhibitor
VL  - 148
SP  - 629
EP  - 639
DO  - 10.1016/j.colsurfb.2016.09.041
ER  - 

@article{
author = "Ignjatović, Nenad and Penov Gaši, Katarina and Wu, Victoria and Ajduković, Jovana and Kojić, Vesna V. and Vasiljević-Radović, Dana and Kuzmanović, Maja and Uskoković, Vuk and Uskoković, Dragan P.",
year = "2016",
abstract = "In an earlier study we demonstrated that hydroxyapatite nanoparticles coated with chitosan-poly(d,l)-lactide-co-glycolide (HAp/Ch-PLGA) target lungs following their intravenous injection into mice. In this study we utilize an emulsification process and freeze drying to load the composite HAp/Ch-PLGA particles with 17β-hydroxy-17α-picolyl-androst-5-en-3β-yl-acetate (A), a chemotherapeutic derivative of androstane and a novel compound with a selective anticancer activity against lung cancer cells. 1H NMR and 13C NMR techniques confirmed the intact structure of the derivative A following its entrapment within HAp/Ch-PLGA particles. The thermogravimetric and differential thermal analyses coupled with mass spectrometry were used to assess the thermal degradation products and properties of A-loaded HAp/Ch-PLGA. The loading efficiency, as indicated by the comparison of enthalpies of phase transitions in pure A and A-loaded HAp/Ch-PLGA, equaled 7.47 wt.%. The release of A from HAp/Ch-PLGA was sustained, neither exhibiting a burst release nor plateauing after three weeks. Atomic force microscopy and particle size distribution analyses were used to confirm that the particles were spherical with a uniform size distribution of d50 = 168 nm. In vitro cytotoxicity testing of A-loaded HAp/Ch-PLGA using MTT and trypan blue dye exclusion assays demonstrated that the particles were cytotoxic to the A549 human lung carcinoma cell line (46 ± 2%), while simultaneously preserving high viability (83 ± 3%) of regular MRC5 human lung fibroblasts and causing no harm to primary mouse lung fibroblasts. In conclusion, composite A-loaded HAp/Ch-PLGA particles could be seen as promising drug delivery platforms for selective cancer therapies, targeting malignant cells for destruction, while having a significantly lesser cytotoxic effect on the healthy cells.",
journal = "Colloids and Surfaces B: Biointerfaces",
title = "Selective anticancer activity of hydroxyapatite/chitosan-poly(D,L)-lactide-co-glycolide particles loaded with an androstane-based cancer inhibitor",
volume = "148",
pages = "629-639",
doi = "10.1016/j.colsurfb.2016.09.041"
}

Ignjatović, N., Penov Gaši, K., Wu, V., Ajduković, J., Kojić, V. V., Vasiljević-Radović, D., Kuzmanović, M., Uskoković, V.,& Uskoković, D. P.. (2016). Selective anticancer activity of hydroxyapatite/chitosan-poly(D,L)-lactide-co-glycolide particles loaded with an androstane-based cancer inhibitor. in Colloids and Surfaces B: Biointerfaces, 148, 629-639.
https://doi.org/10.1016/j.colsurfb.2016.09.041

Ignjatović N, Penov Gaši K, Wu V, Ajduković J, Kojić VV, Vasiljević-Radović D, Kuzmanović M, Uskoković V, Uskoković DP. Selective anticancer activity of hydroxyapatite/chitosan-poly(D,L)-lactide-co-glycolide particles loaded with an androstane-based cancer inhibitor. in Colloids and Surfaces B: Biointerfaces. 2016;148:629-639.
doi:10.1016/j.colsurfb.2016.09.041 .

Ignjatović, Nenad, Penov Gaši, Katarina, Wu, Victoria, Ajduković, Jovana, Kojić, Vesna V., Vasiljević-Radović, Dana, Kuzmanović, Maja, Uskoković, Vuk, Uskoković, Dragan P., "Selective anticancer activity of hydroxyapatite/chitosan-poly(D,L)-lactide-co-glycolide particles loaded with an androstane-based cancer inhibitor" in Colloids and Surfaces B: Biointerfaces, 148 (2016):629-639,
https://doi.org/10.1016/j.colsurfb.2016.09.041 . .

TY  - CONF
AU  - Ignjatović, Nenad
AU  - Penov Gaši, Katarina
AU  - Wu, Victoria
AU  - Ajduković, Jovana
AU  - Kojić, Vesna V.
AU  - Vasiljević-Radović, Dana
AU  - Uskoković, Vuk
AU  - Uskoković, Dragan
PY  - 2016
UR  - http://dais.sanu.ac.rs/123456789/896
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/2864
AB  - The applicative potential of synthetic calcium phosphates, especially hydroxyapatite (HAp), has become intensely broadened in the past 10 years, from bone tissue engineering to multiple other fields of biomedicine. Previously we have shown that hydroxyapatite nanoparticles coated with chitosan-poly(D,L)-lactide-co-glycolide (HAp/Ch-PLGA) target lungs following their intravenous administration into mice. For this purpose radioactive 125-Iodine (125I), a low energy gamma emitter, was used to develop a novel in situ method for radiolabeling of particles and investigation of their biodistribution. In this study we utilize an emulsification process and freeze drying to load the composite particles based on hydroxyapatite nanocarrier, chitosane and poly(lactic-co-glycolic acid) with 17β- hydroxy-17α-picolyl-androst-5-en-3β-acetate (A), a chemotherapeutic derivative of androstane. The picolyl androstane derivatives showed high potency in the cell inhibitors of hormonedependent cancers (adenocarcinoma, prostate cancer, cervix carcinoma, colon cancer, etc.). 1H NMR, 13C NMR and high-resolution time-of-flight mass spectrometry (MS) techniques confirmed the intact structure of the derivative A following its entrapment within HAp/Ch-PLGA particles. The synthesized particles of A-loaded HAp/Ch-PLGA were found to be spherical in shape with a uniform size distribution of d50=168 nm. The release of A from HAp/Ch-PLGA was sustained, with no burst release or plateauing after three weeks. The obtained results of the DET and MTT tests show that the particles of A-loaded HAp/Ch-PLGA exhibit almost three times higher cytotoxicity towards lung adenocarcinoma cells (A549) than towards healthy cells (MRC5), while at the same time allowing twice as fast recovery of healthy cells. We have also analyzed the period of recovery of healthy, as well as cancer cells, following the treatment with A-loaded HAp/Ch-PLGA. After treatment with A-loaded HAp/Ch-PLGA, healthy cells recover twice as fast as the malignant ones. Immunofluorescent staining of primary fibroblasts interacting with HAp/Ch-PLGA and A-HAp/Ch-PLGA particles demonstrates no negative morphological or proliferative effects on cells.
PB  - Belgrade : Materials Research Society of Serbia
C3  - Programme and The Book of Abstracts / Eighteenth Annual Conference YUCOMAT 2016, Herceg Novi, September 5-10, 2016
T1  - Tumor-selective hybrid system based on hydroxyapatite nanocarrier, chitosan, poly(lactic-co-glycolic acid) and androstan derivate
SP  - 27
EP  - 27
UR  - https://hdl.handle.net/21.15107/rcub_dais_896
ER  - 

@conference{
author = "Ignjatović, Nenad and Penov Gaši, Katarina and Wu, Victoria and Ajduković, Jovana and Kojić, Vesna V. and Vasiljević-Radović, Dana and Uskoković, Vuk and Uskoković, Dragan",
year = "2016",
abstract = "The applicative potential of synthetic calcium phosphates, especially hydroxyapatite (HAp), has become intensely broadened in the past 10 years, from bone tissue engineering to multiple other fields of biomedicine. Previously we have shown that hydroxyapatite nanoparticles coated with chitosan-poly(D,L)-lactide-co-glycolide (HAp/Ch-PLGA) target lungs following their intravenous administration into mice. For this purpose radioactive 125-Iodine (125I), a low energy gamma emitter, was used to develop a novel in situ method for radiolabeling of particles and investigation of their biodistribution. In this study we utilize an emulsification process and freeze drying to load the composite particles based on hydroxyapatite nanocarrier, chitosane and poly(lactic-co-glycolic acid) with 17β- hydroxy-17α-picolyl-androst-5-en-3β-acetate (A), a chemotherapeutic derivative of androstane. The picolyl androstane derivatives showed high potency in the cell inhibitors of hormonedependent cancers (adenocarcinoma, prostate cancer, cervix carcinoma, colon cancer, etc.). 1H NMR, 13C NMR and high-resolution time-of-flight mass spectrometry (MS) techniques confirmed the intact structure of the derivative A following its entrapment within HAp/Ch-PLGA particles. The synthesized particles of A-loaded HAp/Ch-PLGA were found to be spherical in shape with a uniform size distribution of d50=168 nm. The release of A from HAp/Ch-PLGA was sustained, with no burst release or plateauing after three weeks. The obtained results of the DET and MTT tests show that the particles of A-loaded HAp/Ch-PLGA exhibit almost three times higher cytotoxicity towards lung adenocarcinoma cells (A549) than towards healthy cells (MRC5), while at the same time allowing twice as fast recovery of healthy cells. We have also analyzed the period of recovery of healthy, as well as cancer cells, following the treatment with A-loaded HAp/Ch-PLGA. After treatment with A-loaded HAp/Ch-PLGA, healthy cells recover twice as fast as the malignant ones. Immunofluorescent staining of primary fibroblasts interacting with HAp/Ch-PLGA and A-HAp/Ch-PLGA particles demonstrates no negative morphological or proliferative effects on cells.",
publisher = "Belgrade : Materials Research Society of Serbia",
journal = "Programme and The Book of Abstracts / Eighteenth Annual Conference YUCOMAT 2016, Herceg Novi, September 5-10, 2016",
title = "Tumor-selective hybrid system based on hydroxyapatite nanocarrier, chitosan, poly(lactic-co-glycolic acid) and androstan derivate",
pages = "27-27",
url = "https://hdl.handle.net/21.15107/rcub_dais_896"
}

Ignjatović, N., Penov Gaši, K., Wu, V., Ajduković, J., Kojić, V. V., Vasiljević-Radović, D., Uskoković, V.,& Uskoković, D.. (2016). Tumor-selective hybrid system based on hydroxyapatite nanocarrier, chitosan, poly(lactic-co-glycolic acid) and androstan derivate. in Programme and The Book of Abstracts / Eighteenth Annual Conference YUCOMAT 2016, Herceg Novi, September 5-10, 2016
Belgrade : Materials Research Society of Serbia., 27-27.
https://hdl.handle.net/21.15107/rcub_dais_896

Ignjatović N, Penov Gaši K, Wu V, Ajduković J, Kojić VV, Vasiljević-Radović D, Uskoković V, Uskoković D. Tumor-selective hybrid system based on hydroxyapatite nanocarrier, chitosan, poly(lactic-co-glycolic acid) and androstan derivate. in Programme and The Book of Abstracts / Eighteenth Annual Conference YUCOMAT 2016, Herceg Novi, September 5-10, 2016. 2016;:27-27.
https://hdl.handle.net/21.15107/rcub_dais_896 .

Ignjatović, Nenad, Penov Gaši, Katarina, Wu, Victoria, Ajduković, Jovana, Kojić, Vesna V., Vasiljević-Radović, Dana, Uskoković, Vuk, Uskoković, Dragan, "Tumor-selective hybrid system based on hydroxyapatite nanocarrier, chitosan, poly(lactic-co-glycolic acid) and androstan derivate" in Programme and The Book of Abstracts / Eighteenth Annual Conference YUCOMAT 2016, Herceg Novi, September 5-10, 2016 (2016):27-27,
https://hdl.handle.net/21.15107/rcub_dais_896 .

TY  - JOUR
AU  - Nastasović, Aleksandra
AU  - Ignjatović, Nenad
AU  - Uskoković, Dragan P.
AU  - Markovic, Dana D.
AU  - Ekmeščić, Bojana
AU  - Maksin, Danijela
AU  - Onjia, Antonije E.
PY  - 2014
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/1598
AB  - Inverse gas chromatography at infinite dilution was applied to determine the thermodynamic interactions of poly(l-lactide) (PLLA) and the composite of biphasic calcium phosphate and PLLA (BCP/PLLA). The specific retention volumes, , of 11 organic compounds of different chemical nature and polarity (non-polar, donor or acceptor) were determined in the temperature range of 308-378 K for PLLA and 308-398 K for BCP/PLLA. The weight fraction activity coefficients of test sorbates, , and the Flory-Huggins interaction parameters, , were estimated and discussed in terms of interactions of the sorbates with PLLA and BCP/PLLA. Also, the partial molar free energy, , the partial molar heat of mixing, , the sorption molar free energy, , the sorption enthalpy, , and the sorption entropy, , were analyzed. A different chromatographic behavior of the two investigated samples, PLLA and BCP/PLLA, was observed. The values of indicated n-alkanes, diethyl ether, tetrahydrofurane (THF), cyclohexane, benzene, dioxane (except for 338 K), and ethyl acetate (EtAc) (except for 338 K) as non-solvents, and chloroform (CHCl3) as good solvent (except for 378 K) for PLLA. For BCP/PLLA, CHCl3, EtAc (for 378 K), dioxane (except for 378 K), and THF were indicated as good solvents.
PB  - Springer, New York
T2  - Journal of Materials Science
T1  - Determination of thermodynamic interactions of polylactide and biphasic calcium phosphate/polylactidecomposite by inverse gas chromatography at infinite dilution
VL  - 49
IS  - 14
SP  - 5076
EP  - 5086
DO  - 10.1007/s10853-014-8214-3
ER  - 

@article{
author = "Nastasović, Aleksandra and Ignjatović, Nenad and Uskoković, Dragan P. and Markovic, Dana D. and Ekmeščić, Bojana and Maksin, Danijela and Onjia, Antonije E.",
year = "2014",
abstract = "Inverse gas chromatography at infinite dilution was applied to determine the thermodynamic interactions of poly(l-lactide) (PLLA) and the composite of biphasic calcium phosphate and PLLA (BCP/PLLA). The specific retention volumes, , of 11 organic compounds of different chemical nature and polarity (non-polar, donor or acceptor) were determined in the temperature range of 308-378 K for PLLA and 308-398 K for BCP/PLLA. The weight fraction activity coefficients of test sorbates, , and the Flory-Huggins interaction parameters, , were estimated and discussed in terms of interactions of the sorbates with PLLA and BCP/PLLA. Also, the partial molar free energy, , the partial molar heat of mixing, , the sorption molar free energy, , the sorption enthalpy, , and the sorption entropy, , were analyzed. A different chromatographic behavior of the two investigated samples, PLLA and BCP/PLLA, was observed. The values of indicated n-alkanes, diethyl ether, tetrahydrofurane (THF), cyclohexane, benzene, dioxane (except for 338 K), and ethyl acetate (EtAc) (except for 338 K) as non-solvents, and chloroform (CHCl3) as good solvent (except for 378 K) for PLLA. For BCP/PLLA, CHCl3, EtAc (for 378 K), dioxane (except for 378 K), and THF were indicated as good solvents.",
publisher = "Springer, New York",
journal = "Journal of Materials Science",
title = "Determination of thermodynamic interactions of polylactide and biphasic calcium phosphate/polylactidecomposite by inverse gas chromatography at infinite dilution",
volume = "49",
number = "14",
pages = "5076-5086",
doi = "10.1007/s10853-014-8214-3"
}

Nastasović, A., Ignjatović, N., Uskoković, D. P., Markovic, D. D., Ekmeščić, B., Maksin, D.,& Onjia, A. E.. (2014). Determination of thermodynamic interactions of polylactide and biphasic calcium phosphate/polylactidecomposite by inverse gas chromatography at infinite dilution. in Journal of Materials Science
Springer, New York., 49(14), 5076-5086.
https://doi.org/10.1007/s10853-014-8214-3

Nastasović A, Ignjatović N, Uskoković DP, Markovic DD, Ekmeščić B, Maksin D, Onjia AE. Determination of thermodynamic interactions of polylactide and biphasic calcium phosphate/polylactidecomposite by inverse gas chromatography at infinite dilution. in Journal of Materials Science. 2014;49(14):5076-5086.
doi:10.1007/s10853-014-8214-3 .

Nastasović, Aleksandra, Ignjatović, Nenad, Uskoković, Dragan P., Markovic, Dana D., Ekmeščić, Bojana, Maksin, Danijela, Onjia, Antonije E., "Determination of thermodynamic interactions of polylactide and biphasic calcium phosphate/polylactidecomposite by inverse gas chromatography at infinite dilution" in Journal of Materials Science, 49, no. 14 (2014):5076-5086,
https://doi.org/10.1007/s10853-014-8214-3 . .