TY  - JOUR
AU  - Marković, Zoran M.
AU  - Budimir, Milica
AU  - Danko, Martin
AU  - Milivojević, Dušan
AU  - Kubat, Pavel
AU  - Zmejkoski, Danica
AU  - Pavlović, Vladimir B.
AU  - Mojsin, Marija
AU  - Stevanović, Milena J.
AU  - Todorović-Marković, Biljana
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10632
AB  - Carbon quantum dots as a novel type of carbon nanomaterials have attracted the attention of many researchers because of their unique optical, antibacterial, and anticancer properties as well as their biocompatibility. In this study, for the first time, carbon quantum dots were prepared from o-phenylenediamine dissolved in toluene by a solvothermal route. Subsequently, the prepared carbon quantum dots were encapsulated into polyurethane films by a swelling–encapsulation–shrink method. Analyses of the results obtained by different characterization methods (AFM, TEM, EDS, FTIR, photoluminescence, and EPR) indicate the significant influence of the precursor on structural, chemical, and optical properties. Antibacterial and cytotoxicity tests showed that these dots did not have any antibacterial potential, because of the low extent of reactive oxygen species production, and showed low dark cytotoxicity. By investigating the cellular uptake, it was established that these dots penetrated the HeLa cells and could be used as probes for bioimaging.
T2  - Beilstein Journal of Nanotechnology
T1  - Structural, optical, and bioimaging characterization of carbon quantum dots solvothermally synthesized from o-phenylenediamine
VL  - 14
IS  - 1
SP  - 165
EP  - 174
DO  - 10.3762/bjnano.14.17
ER  - 

@article{
author = "Marković, Zoran M. and Budimir, Milica and Danko, Martin and Milivojević, Dušan and Kubat, Pavel and Zmejkoski, Danica and Pavlović, Vladimir B. and Mojsin, Marija and Stevanović, Milena J. and Todorović-Marković, Biljana",
year = "2023",
abstract = "Carbon quantum dots as a novel type of carbon nanomaterials have attracted the attention of many researchers because of their unique optical, antibacterial, and anticancer properties as well as their biocompatibility. In this study, for the first time, carbon quantum dots were prepared from o-phenylenediamine dissolved in toluene by a solvothermal route. Subsequently, the prepared carbon quantum dots were encapsulated into polyurethane films by a swelling–encapsulation–shrink method. Analyses of the results obtained by different characterization methods (AFM, TEM, EDS, FTIR, photoluminescence, and EPR) indicate the significant influence of the precursor on structural, chemical, and optical properties. Antibacterial and cytotoxicity tests showed that these dots did not have any antibacterial potential, because of the low extent of reactive oxygen species production, and showed low dark cytotoxicity. By investigating the cellular uptake, it was established that these dots penetrated the HeLa cells and could be used as probes for bioimaging.",
journal = "Beilstein Journal of Nanotechnology",
title = "Structural, optical, and bioimaging characterization of carbon quantum dots solvothermally synthesized from o-phenylenediamine",
volume = "14",
number = "1",
pages = "165-174",
doi = "10.3762/bjnano.14.17"
}

Marković, Z. M., Budimir, M., Danko, M., Milivojević, D., Kubat, P., Zmejkoski, D., Pavlović, V. B., Mojsin, M., Stevanović, M. J.,& Todorović-Marković, B.. (2023). Structural, optical, and bioimaging characterization of carbon quantum dots solvothermally synthesized from o-phenylenediamine. in Beilstein Journal of Nanotechnology, 14(1), 165-174.
https://doi.org/10.3762/bjnano.14.17

Marković ZM, Budimir M, Danko M, Milivojević D, Kubat P, Zmejkoski D, Pavlović VB, Mojsin M, Stevanović MJ, Todorović-Marković B. Structural, optical, and bioimaging characterization of carbon quantum dots solvothermally synthesized from o-phenylenediamine. in Beilstein Journal of Nanotechnology. 2023;14(1):165-174.
doi:10.3762/bjnano.14.17 .

Marković, Zoran M., Budimir, Milica, Danko, Martin, Milivojević, Dušan, Kubat, Pavel, Zmejkoski, Danica, Pavlović, Vladimir B., Mojsin, Marija, Stevanović, Milena J., Todorović-Marković, Biljana, "Structural, optical, and bioimaging characterization of carbon quantum dots solvothermally synthesized from o-phenylenediamine" in Beilstein Journal of Nanotechnology, 14, no. 1 (2023):165-174,
https://doi.org/10.3762/bjnano.14.17 . .

TY  - JOUR
AU  - Marković, Zoran M.
AU  - Mišović, Aleksandra
AU  - Zmejkoski, Danica
AU  - Zdravković, Nemanja M.
AU  - Kovač, Janez
AU  - Bajuk-Bogdanović, Danica
AU  - Milivojević, Dušan
AU  - Mojsin, Marija
AU  - Stevanović, Milena
AU  - Pavlović, Vladimir B.
AU  - Todorović-Marković, Biljana
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/11075
AB  - Nowadays, it is a great challenge to develop new medicines for treating various infectious diseases. The treatment of these diseases is of utmost interest to further prevent the development of multi-drug resistance in different pathogens. Carbon quantum dots, as a new member of the carbon nanomaterials family, can potentially be used as a highly promising visible-light-triggered antibacterial agent. In this work, the results of antibacterial and cytotoxic activities of gamma-ray-irradiated carbon quantum dots are presented. Carbon quantum dots (CQDs) were synthesized from citric acid by a pyrolysis procedure and irradiated by gamma rays at different doses (25, 50, 100 and 200 kGy). Structure, chemical composition and optical properties were investigated by atomic force microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, UV-Vis spectrometry and photoluminescence. Structural analysis showed that CQDs have a spherical-like shape and dose-dependent average diameters and heights. Antibacterial tests showed that all irradiated dots had antibacterial activity but CQDs irradiated with dose of 100 kGy had antibacterial activity against all seven pathogen-reference bacterial strains. Gamma-ray-modified CQDs did not show any cytotoxicity toward human fetal-originated MRC-5 cells. Moreover, fluorescence microscopy showed excellent cellular uptake of CQDs irradiated with doses of 25 and 200 kGy into MRC-5 cells.
T2  - Antibiotics
T1  - Employing Gamma-Ray-Modified Carbon Quantum Dots to Combat a Wide Range of Bacteria
VL  - 12
IS  - 5
SP  - 919
DO  - 10.3390/antibiotics12050919
ER  - 

@article{
author = "Marković, Zoran M. and Mišović, Aleksandra and Zmejkoski, Danica and Zdravković, Nemanja M. and Kovač, Janez and Bajuk-Bogdanović, Danica and Milivojević, Dušan and Mojsin, Marija and Stevanović, Milena and Pavlović, Vladimir B. and Todorović-Marković, Biljana",
year = "2023",
abstract = "Nowadays, it is a great challenge to develop new medicines for treating various infectious diseases. The treatment of these diseases is of utmost interest to further prevent the development of multi-drug resistance in different pathogens. Carbon quantum dots, as a new member of the carbon nanomaterials family, can potentially be used as a highly promising visible-light-triggered antibacterial agent. In this work, the results of antibacterial and cytotoxic activities of gamma-ray-irradiated carbon quantum dots are presented. Carbon quantum dots (CQDs) were synthesized from citric acid by a pyrolysis procedure and irradiated by gamma rays at different doses (25, 50, 100 and 200 kGy). Structure, chemical composition and optical properties were investigated by atomic force microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, UV-Vis spectrometry and photoluminescence. Structural analysis showed that CQDs have a spherical-like shape and dose-dependent average diameters and heights. Antibacterial tests showed that all irradiated dots had antibacterial activity but CQDs irradiated with dose of 100 kGy had antibacterial activity against all seven pathogen-reference bacterial strains. Gamma-ray-modified CQDs did not show any cytotoxicity toward human fetal-originated MRC-5 cells. Moreover, fluorescence microscopy showed excellent cellular uptake of CQDs irradiated with doses of 25 and 200 kGy into MRC-5 cells.",
journal = "Antibiotics",
title = "Employing Gamma-Ray-Modified Carbon Quantum Dots to Combat a Wide Range of Bacteria",
volume = "12",
number = "5",
pages = "919",
doi = "10.3390/antibiotics12050919"
}

Marković, Z. M., Mišović, A., Zmejkoski, D., Zdravković, N. M., Kovač, J., Bajuk-Bogdanović, D., Milivojević, D., Mojsin, M., Stevanović, M., Pavlović, V. B.,& Todorović-Marković, B.. (2023). Employing Gamma-Ray-Modified Carbon Quantum Dots to Combat a Wide Range of Bacteria. in Antibiotics, 12(5), 919.
https://doi.org/10.3390/antibiotics12050919

Marković ZM, Mišović A, Zmejkoski D, Zdravković NM, Kovač J, Bajuk-Bogdanović D, Milivojević D, Mojsin M, Stevanović M, Pavlović VB, Todorović-Marković B. Employing Gamma-Ray-Modified Carbon Quantum Dots to Combat a Wide Range of Bacteria. in Antibiotics. 2023;12(5):919.
doi:10.3390/antibiotics12050919 .

Marković, Zoran M., Mišović, Aleksandra, Zmejkoski, Danica, Zdravković, Nemanja M., Kovač, Janez, Bajuk-Bogdanović, Danica, Milivojević, Dušan, Mojsin, Marija, Stevanović, Milena, Pavlović, Vladimir B., Todorović-Marković, Biljana, "Employing Gamma-Ray-Modified Carbon Quantum Dots to Combat a Wide Range of Bacteria" in Antibiotics, 12, no. 5 (2023):919,
https://doi.org/10.3390/antibiotics12050919 . .

TY  - JOUR
AU  - Marković, Zoran M.
AU  - Kováčová, Mária
AU  - Jeremić, Sanja
AU  - Nagy, Štefan
AU  - Milivojević, Dušan
AU  - Kubat, Pavel
AU  - Kleinová, Angela
AU  - Budimir, Milica
AU  - Mojsin, Marija
AU  - Stevanović, Milena J.
AU  - Annušová, Adriana
AU  - Špitalský, Zdeno
AU  - Todorović-Marković, Biljana
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10517
AB  - Development of new types of antimicrobial coatings is of utmost importance due to increasing problems with pathogen transmission from various infectious surfaces to human beings. In this study, new types of highly potent antimicrobial polyurethane composite films encapsulated by hydrophobic riboflavin-based carbon polymer dots are presented. Detailed structural, optical, antimicrobial, and cytotoxic investigations of these composites were conducted. Low-power blue light triggered the composites to eradicate Escherichia coli in 30 min, whereas the same effect toward Staphylococcus aureus was reached after 60 min. These composites also show low toxicity against MRC-5 cells. In this way, RF-CPD composites can be used for sterilization of highly touched objects in the healthcare industry.
T2  - Nanomaterials
T1  - Highly Efficient Antibacterial Polymer Composites Based on Hydrophobic Riboflavin Carbon Polymerized Dots
VL  - 12
IS  - 22
SP  - 4070
DO  - 10.3390/nano12224070
ER  - 

@article{
author = "Marković, Zoran M. and Kováčová, Mária and Jeremić, Sanja and Nagy, Štefan and Milivojević, Dušan and Kubat, Pavel and Kleinová, Angela and Budimir, Milica and Mojsin, Marija and Stevanović, Milena J. and Annušová, Adriana and Špitalský, Zdeno and Todorović-Marković, Biljana",
year = "2022",
abstract = "Development of new types of antimicrobial coatings is of utmost importance due to increasing problems with pathogen transmission from various infectious surfaces to human beings. In this study, new types of highly potent antimicrobial polyurethane composite films encapsulated by hydrophobic riboflavin-based carbon polymer dots are presented. Detailed structural, optical, antimicrobial, and cytotoxic investigations of these composites were conducted. Low-power blue light triggered the composites to eradicate Escherichia coli in 30 min, whereas the same effect toward Staphylococcus aureus was reached after 60 min. These composites also show low toxicity against MRC-5 cells. In this way, RF-CPD composites can be used for sterilization of highly touched objects in the healthcare industry.",
journal = "Nanomaterials",
title = "Highly Efficient Antibacterial Polymer Composites Based on Hydrophobic Riboflavin Carbon Polymerized Dots",
volume = "12",
number = "22",
pages = "4070",
doi = "10.3390/nano12224070"
}

Marković, Z. M., Kováčová, M., Jeremić, S., Nagy, Š., Milivojević, D., Kubat, P., Kleinová, A., Budimir, M., Mojsin, M., Stevanović, M. J., Annušová, A., Špitalský, Z.,& Todorović-Marković, B.. (2022). Highly Efficient Antibacterial Polymer Composites Based on Hydrophobic Riboflavin Carbon Polymerized Dots. in Nanomaterials, 12(22), 4070.
https://doi.org/10.3390/nano12224070

Marković ZM, Kováčová M, Jeremić S, Nagy Š, Milivojević D, Kubat P, Kleinová A, Budimir M, Mojsin M, Stevanović MJ, Annušová A, Špitalský Z, Todorović-Marković B. Highly Efficient Antibacterial Polymer Composites Based on Hydrophobic Riboflavin Carbon Polymerized Dots. in Nanomaterials. 2022;12(22):4070.
doi:10.3390/nano12224070 .

Marković, Zoran M., Kováčová, Mária, Jeremić, Sanja, Nagy, Štefan, Milivojević, Dušan, Kubat, Pavel, Kleinová, Angela, Budimir, Milica, Mojsin, Marija, Stevanović, Milena J., Annušová, Adriana, Špitalský, Zdeno, Todorović-Marković, Biljana, "Highly Efficient Antibacterial Polymer Composites Based on Hydrophobic Riboflavin Carbon Polymerized Dots" in Nanomaterials, 12, no. 22 (2022):4070,
https://doi.org/10.3390/nano12224070 . .

TY  - JOUR
AU  - Dorontić, Slađana
AU  - Bonasera, Aurelio
AU  - Scopelliti, Michelangelo
AU  - Mojsin, Marija
AU  - Stevanović, Milena J.
AU  - Marković, Olivera
AU  - Jovanović, Svetlana P.
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10440
AB  - Large amounts of hazardous and toxic substances in the environment require non-toxic, cheap, easy, rapid, and sensitive methods for their detection. Blue luminescent graphene quantum dots (GQDs) were produced by electrochemical cleavage of graphite electrodes followed by gamma irradiation in the presence of ethylenediamine (EDA). Modified dots were able to detect metal ions (Co2+, Pd2+, Fe3+) due to photoluminescence quenching. The highest sensitivity was detected for the sample irradiated at a dose of 25 kGy. The limits of detection (LODs) were 1.79, 2.55, and 0.66 μmol L−1 for Co2+, Fe3+, and Pd2+, respectively. It was observed that GQDs irradiated at 200 kGy act as an ultra-sensitive turn-on probe for Malathion detection with LOD of 94 nmol L−1. Atomic force microscopy images proved the aggregation of GQDs in the presence of the investigated metal ions. Results obtained by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and LIVE/DEAD cytotoxicity test indicated that GQDs irradiated with EDA are not toxic towards MRC-5 cells, which makes them a promising, eco-friendly and safe material for sensing application.
T2  - Journal of Luminescence
T1  - Blue luminescent amino-functionalized graphene quantum dots as a responsive material for potential detection of metal ions and malathion
VL  - 252
SP  - 119311
DO  - 10.1016/j.jlumin.2022.119311
ER  - 

@article{
author = "Dorontić, Slađana and Bonasera, Aurelio and Scopelliti, Michelangelo and Mojsin, Marija and Stevanović, Milena J. and Marković, Olivera and Jovanović, Svetlana P.",
year = "2022",
abstract = "Large amounts of hazardous and toxic substances in the environment require non-toxic, cheap, easy, rapid, and sensitive methods for their detection. Blue luminescent graphene quantum dots (GQDs) were produced by electrochemical cleavage of graphite electrodes followed by gamma irradiation in the presence of ethylenediamine (EDA). Modified dots were able to detect metal ions (Co2+, Pd2+, Fe3+) due to photoluminescence quenching. The highest sensitivity was detected for the sample irradiated at a dose of 25 kGy. The limits of detection (LODs) were 1.79, 2.55, and 0.66 μmol L−1 for Co2+, Fe3+, and Pd2+, respectively. It was observed that GQDs irradiated at 200 kGy act as an ultra-sensitive turn-on probe for Malathion detection with LOD of 94 nmol L−1. Atomic force microscopy images proved the aggregation of GQDs in the presence of the investigated metal ions. Results obtained by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and LIVE/DEAD cytotoxicity test indicated that GQDs irradiated with EDA are not toxic towards MRC-5 cells, which makes them a promising, eco-friendly and safe material for sensing application.",
journal = "Journal of Luminescence",
title = "Blue luminescent amino-functionalized graphene quantum dots as a responsive material for potential detection of metal ions and malathion",
volume = "252",
pages = "119311",
doi = "10.1016/j.jlumin.2022.119311"
}

Dorontić, S., Bonasera, A., Scopelliti, M., Mojsin, M., Stevanović, M. J., Marković, O.,& Jovanović, S. P.. (2022). Blue luminescent amino-functionalized graphene quantum dots as a responsive material for potential detection of metal ions and malathion. in Journal of Luminescence, 252, 119311.
https://doi.org/10.1016/j.jlumin.2022.119311

Dorontić S, Bonasera A, Scopelliti M, Mojsin M, Stevanović MJ, Marković O, Jovanović SP. Blue luminescent amino-functionalized graphene quantum dots as a responsive material for potential detection of metal ions and malathion. in Journal of Luminescence. 2022;252:119311.
doi:10.1016/j.jlumin.2022.119311 .

Dorontić, Slađana, Bonasera, Aurelio, Scopelliti, Michelangelo, Mojsin, Marija, Stevanović, Milena J., Marković, Olivera, Jovanović, Svetlana P., "Blue luminescent amino-functionalized graphene quantum dots as a responsive material for potential detection of metal ions and malathion" in Journal of Luminescence, 252 (2022):119311,
https://doi.org/10.1016/j.jlumin.2022.119311 . .

TY  - JOUR
AU  - Milenković, Mila
AU  - Mišović, Aleksandra
AU  - Jovanović, Dragana J.
AU  - Popović-Bijelić, Ana D.
AU  - Ciasca, Gabriele
AU  - Romanò, Sabrina
AU  - Bonasera, Aurelio
AU  - Mojsin, Marija
AU  - Pejić, Jelena
AU  - Stevanović, Milena J.
AU  - Jovanović, Svetlana P.
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9873
AB  - Nowadays, a larger number of aggressive and corrosive chemical reagents as well as toxic solvents are used to achieve structural modification and cleaning of the final products. These lead to the production of residual, waste chemicals, which are often reactive, cancerogenic, and toxic to the environment. This study shows a new approach to the modification of graphene quantum dots (GQDs) using gamma irradiation where the usage of reagents was avoided. We achieved the incorporation of S and N atoms in the GQD structure by selecting an aqueous solution of L-cysteine as an irradiation medium. GQDs were exposed to gamma-irradiation at doses of 25, 50 and 200 kGy. After irradiation, the optical, structural, and morphological properties, as well as the possibility of their use as an agent in bioimaging and photodynamic therapy, were studied. We measured an enhanced quantum yield of photoluminescence with the highest dose of 25 kGy (21.60%). Both S- and N-functional groups were detected in all gamma-irradiated GQDs: amino, amide, thiol, and thione. Spin trap electron paramagnetic resonance showed that GQDs irradiated with 25 kGy can generate singlet oxygen upon illumination. Bioimaging on HeLa cells showed the best visibility for cells treated with GQDs irradiated with 25 kGy, while cytotoxicity was not detected after treatment of HeLa cells with gamma-irradiated GQDs.
T2  - Nanomaterials
T1  - Facile synthesis of L-cysteine functionalized graphene quantum dots as a bioimaging and photosensitive agent
VL  - 11
IS  - 8
SP  - 1879
DO  - 10.3390/nano11081879
ER  - 

@article{
author = "Milenković, Mila and Mišović, Aleksandra and Jovanović, Dragana J. and Popović-Bijelić, Ana D. and Ciasca, Gabriele and Romanò, Sabrina and Bonasera, Aurelio and Mojsin, Marija and Pejić, Jelena and Stevanović, Milena J. and Jovanović, Svetlana P.",
year = "2021",
abstract = "Nowadays, a larger number of aggressive and corrosive chemical reagents as well as toxic solvents are used to achieve structural modification and cleaning of the final products. These lead to the production of residual, waste chemicals, which are often reactive, cancerogenic, and toxic to the environment. This study shows a new approach to the modification of graphene quantum dots (GQDs) using gamma irradiation where the usage of reagents was avoided. We achieved the incorporation of S and N atoms in the GQD structure by selecting an aqueous solution of L-cysteine as an irradiation medium. GQDs were exposed to gamma-irradiation at doses of 25, 50 and 200 kGy. After irradiation, the optical, structural, and morphological properties, as well as the possibility of their use as an agent in bioimaging and photodynamic therapy, were studied. We measured an enhanced quantum yield of photoluminescence with the highest dose of 25 kGy (21.60%). Both S- and N-functional groups were detected in all gamma-irradiated GQDs: amino, amide, thiol, and thione. Spin trap electron paramagnetic resonance showed that GQDs irradiated with 25 kGy can generate singlet oxygen upon illumination. Bioimaging on HeLa cells showed the best visibility for cells treated with GQDs irradiated with 25 kGy, while cytotoxicity was not detected after treatment of HeLa cells with gamma-irradiated GQDs.",
journal = "Nanomaterials",
title = "Facile synthesis of L-cysteine functionalized graphene quantum dots as a bioimaging and photosensitive agent",
volume = "11",
number = "8",
pages = "1879",
doi = "10.3390/nano11081879"
}

Milenković, M., Mišović, A., Jovanović, D. J., Popović-Bijelić, A. D., Ciasca, G., Romanò, S., Bonasera, A., Mojsin, M., Pejić, J., Stevanović, M. J.,& Jovanović, S. P.. (2021). Facile synthesis of L-cysteine functionalized graphene quantum dots as a bioimaging and photosensitive agent. in Nanomaterials, 11(8), 1879.
https://doi.org/10.3390/nano11081879

Milenković M, Mišović A, Jovanović DJ, Popović-Bijelić AD, Ciasca G, Romanò S, Bonasera A, Mojsin M, Pejić J, Stevanović MJ, Jovanović SP. Facile synthesis of L-cysteine functionalized graphene quantum dots as a bioimaging and photosensitive agent. in Nanomaterials. 2021;11(8):1879.
doi:10.3390/nano11081879 .

Milenković, Mila, Mišović, Aleksandra, Jovanović, Dragana J., Popović-Bijelić, Ana D., Ciasca, Gabriele, Romanò, Sabrina, Bonasera, Aurelio, Mojsin, Marija, Pejić, Jelena, Stevanović, Milena J., Jovanović, Svetlana P., "Facile synthesis of L-cysteine functionalized graphene quantum dots as a bioimaging and photosensitive agent" in Nanomaterials, 11, no. 8 (2021):1879,
https://doi.org/10.3390/nano11081879 . .

TY  - JOUR
AU  - Jovanović, Svetlana P.
AU  - Syrgiannis, Zois
AU  - Budimir, Milica
AU  - Milivojević, Dušan
AU  - Jovanović, Dragana J.
AU  - Pavlović, Vladimir B.
AU  - Papan, Jelena
AU  - Bartenwerfer, Malte
AU  - Mojsin, Marija
AU  - Stevanović, Milena J.
AU  - Todorović-Marković, Biljana
PY  - 2020
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8672
AB  - Due to their low cost and possible green synthesis, high stability and resistance to photobleaching, graphene quantum dots (GQDs) can be considered as one of the class of carbon nanomaterials which may have great potential as an agent for photosensitized oxygen activation. In such a way, GQDs can be used as a theranostic agent in photodynamic therapy. In this work pristine GQDs, GQDs irradiated with gamma rays and GQDs doped with N and N, S atoms are produced using a simple, green approach. By using different techniques (AFM, HR-TEM, SEM-EDS, FTIR, XRD, PL and UV–Vis) we investigated structural and optical properties of the new types of GQDs. We showed that GQDs functionalized with thiourea (GQDs-TU) completely lost the ability to produce singlet oxygen (1O2) upon photoexcitation while functionalization with urea (GQDs-U) improves the capability of GQDs to produce 1O2 upon the same conditions. Thus, presented GQDs modification with urea seems like a promising approach for the production of the efficient photosensitizer. On the opposite, GQDs-TU are efficient [rad]OH quencher. Due to high singlet oxygen production and low cytotoxicity below 100 μg/mL against HeLa cells, GQDs-U is a good candidate as an agent in photodynamic therapy at this concentration. © 2019
T2  - Materials Science and Engineering: C
T1  - Graphene quantum dots as singlet oxygen producer or radical quencher - The matter of functionalization with urea/thiourea
VL  - 109
SP  - 110539
DO  - 10.1016/j.msec.2019.110539
ER  - 

@article{
author = "Jovanović, Svetlana P. and Syrgiannis, Zois and Budimir, Milica and Milivojević, Dušan and Jovanović, Dragana J. and Pavlović, Vladimir B. and Papan, Jelena and Bartenwerfer, Malte and Mojsin, Marija and Stevanović, Milena J. and Todorović-Marković, Biljana",
year = "2020",
abstract = "Due to their low cost and possible green synthesis, high stability and resistance to photobleaching, graphene quantum dots (GQDs) can be considered as one of the class of carbon nanomaterials which may have great potential as an agent for photosensitized oxygen activation. In such a way, GQDs can be used as a theranostic agent in photodynamic therapy. In this work pristine GQDs, GQDs irradiated with gamma rays and GQDs doped with N and N, S atoms are produced using a simple, green approach. By using different techniques (AFM, HR-TEM, SEM-EDS, FTIR, XRD, PL and UV–Vis) we investigated structural and optical properties of the new types of GQDs. We showed that GQDs functionalized with thiourea (GQDs-TU) completely lost the ability to produce singlet oxygen (1O2) upon photoexcitation while functionalization with urea (GQDs-U) improves the capability of GQDs to produce 1O2 upon the same conditions. Thus, presented GQDs modification with urea seems like a promising approach for the production of the efficient photosensitizer. On the opposite, GQDs-TU are efficient [rad]OH quencher. Due to high singlet oxygen production and low cytotoxicity below 100 μg/mL against HeLa cells, GQDs-U is a good candidate as an agent in photodynamic therapy at this concentration. © 2019",
journal = "Materials Science and Engineering: C",
title = "Graphene quantum dots as singlet oxygen producer or radical quencher - The matter of functionalization with urea/thiourea",
volume = "109",
pages = "110539",
doi = "10.1016/j.msec.2019.110539"
}

Jovanović, S. P., Syrgiannis, Z., Budimir, M., Milivojević, D., Jovanović, D. J., Pavlović, V. B., Papan, J., Bartenwerfer, M., Mojsin, M., Stevanović, M. J.,& Todorović-Marković, B.. (2020). Graphene quantum dots as singlet oxygen producer or radical quencher - The matter of functionalization with urea/thiourea. in Materials Science and Engineering: C, 109, 110539.
https://doi.org/10.1016/j.msec.2019.110539

Jovanović SP, Syrgiannis Z, Budimir M, Milivojević D, Jovanović DJ, Pavlović VB, Papan J, Bartenwerfer M, Mojsin M, Stevanović MJ, Todorović-Marković B. Graphene quantum dots as singlet oxygen producer or radical quencher - The matter of functionalization with urea/thiourea. in Materials Science and Engineering: C. 2020;109:110539.
doi:10.1016/j.msec.2019.110539 .

Jovanović, Svetlana P., Syrgiannis, Zois, Budimir, Milica, Milivojević, Dušan, Jovanović, Dragana J., Pavlović, Vladimir B., Papan, Jelena, Bartenwerfer, Malte, Mojsin, Marija, Stevanović, Milena J., Todorović-Marković, Biljana, "Graphene quantum dots as singlet oxygen producer or radical quencher - The matter of functionalization with urea/thiourea" in Materials Science and Engineering: C, 109 (2020):110539,
https://doi.org/10.1016/j.msec.2019.110539 . .

TY  - JOUR
AU  - Marković, Zoran M.
AU  - Jovanović, Svetlana P.
AU  - Mašković, Pavle Z.
AU  - Mojsin, Marija
AU  - Stevanović, Milena J.
AU  - Danko, Martin
AU  - Mičušik, Matej
AU  - Jovanović, Dragana J.
AU  - Kleinova, Angela
AU  - Špitalsky, Zdeno
AU  - Pavlović, Vladimir B.
AU  - Todorović-Marković, Biljana
PY  - 2019
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/8591
AB  - Photoactive materials called photosensitizers can be used for treatment of different types of cancer in combination with light source. In this paper, we have investigated pro-oxidant and antioxidant potentials of four graphene based nanomaterials (graphene oxide-GO, graphene quantum dots-GQDs, carbon quantum dots-CQDs and N-doped carbon quantum dots-N-CQDs) depending on the presence/absence of visible light source. Structural and optical properties of these materials and their potentials for reactive oxygen species generation/quenching are investigated by applying different microscopy and spectroscopy techniques (transmission electron microscopy, FTIR, UV–Vis, photoluminescence, electron paramagnetic resonance). Results show that all types of quantum dots has pro-oxidant and antioxidant potentials whereas GO demonstrated only moderate antioxidant effect. The best free radical scavenger is CQDs sample in the absence of light. CQDs are the best singlet oxygen generator under blue light irradiation as well. To check photo-cytotoxicity of these materials, photo-cytotoxic concentrations of the GO, GQDs, CQDs and N-CQDs were determined for three cellular lines: human rhabdomyosarcoma (RD), cell line derived from human cervix carcinoma Hep2c (HeLa) and fibroblast cell line from murine (L2OB). Cytotoxicity test has indicated that all samples are much less photocytotoxic than cis-diamminedichloroplatinum (cis-DPP). The production method and doping of quantum dots affect the photodynamic activity of tested samples very much.
T2  - Journal of Photochemistry and Photobiology B: Biology
T1  - Graphene oxide size and structure pro-oxidant and antioxidant activity and photoinduced cytotoxicity relation on three cancer cell lines
VL  - 200
SP  - 111647
DO  - 10.1016/j.jphotobiol.2019.111647
ER  - 

@article{
author = "Marković, Zoran M. and Jovanović, Svetlana P. and Mašković, Pavle Z. and Mojsin, Marija and Stevanović, Milena J. and Danko, Martin and Mičušik, Matej and Jovanović, Dragana J. and Kleinova, Angela and Špitalsky, Zdeno and Pavlović, Vladimir B. and Todorović-Marković, Biljana",
year = "2019",
abstract = "Photoactive materials called photosensitizers can be used for treatment of different types of cancer in combination with light source. In this paper, we have investigated pro-oxidant and antioxidant potentials of four graphene based nanomaterials (graphene oxide-GO, graphene quantum dots-GQDs, carbon quantum dots-CQDs and N-doped carbon quantum dots-N-CQDs) depending on the presence/absence of visible light source. Structural and optical properties of these materials and their potentials for reactive oxygen species generation/quenching are investigated by applying different microscopy and spectroscopy techniques (transmission electron microscopy, FTIR, UV–Vis, photoluminescence, electron paramagnetic resonance). Results show that all types of quantum dots has pro-oxidant and antioxidant potentials whereas GO demonstrated only moderate antioxidant effect. The best free radical scavenger is CQDs sample in the absence of light. CQDs are the best singlet oxygen generator under blue light irradiation as well. To check photo-cytotoxicity of these materials, photo-cytotoxic concentrations of the GO, GQDs, CQDs and N-CQDs were determined for three cellular lines: human rhabdomyosarcoma (RD), cell line derived from human cervix carcinoma Hep2c (HeLa) and fibroblast cell line from murine (L2OB). Cytotoxicity test has indicated that all samples are much less photocytotoxic than cis-diamminedichloroplatinum (cis-DPP). The production method and doping of quantum dots affect the photodynamic activity of tested samples very much.",
journal = "Journal of Photochemistry and Photobiology B: Biology",
title = "Graphene oxide size and structure pro-oxidant and antioxidant activity and photoinduced cytotoxicity relation on three cancer cell lines",
volume = "200",
pages = "111647",
doi = "10.1016/j.jphotobiol.2019.111647"
}

Marković, Z. M., Jovanović, S. P., Mašković, P. Z., Mojsin, M., Stevanović, M. J., Danko, M., Mičušik, M., Jovanović, D. J., Kleinova, A., Špitalsky, Z., Pavlović, V. B.,& Todorović-Marković, B.. (2019). Graphene oxide size and structure pro-oxidant and antioxidant activity and photoinduced cytotoxicity relation on three cancer cell lines. in Journal of Photochemistry and Photobiology B: Biology, 200, 111647.
https://doi.org/10.1016/j.jphotobiol.2019.111647

Marković ZM, Jovanović SP, Mašković PZ, Mojsin M, Stevanović MJ, Danko M, Mičušik M, Jovanović DJ, Kleinova A, Špitalsky Z, Pavlović VB, Todorović-Marković B. Graphene oxide size and structure pro-oxidant and antioxidant activity and photoinduced cytotoxicity relation on three cancer cell lines. in Journal of Photochemistry and Photobiology B: Biology. 2019;200:111647.
doi:10.1016/j.jphotobiol.2019.111647 .

Marković, Zoran M., Jovanović, Svetlana P., Mašković, Pavle Z., Mojsin, Marija, Stevanović, Milena J., Danko, Martin, Mičušik, Matej, Jovanović, Dragana J., Kleinova, Angela, Špitalsky, Zdeno, Pavlović, Vladimir B., Todorović-Marković, Biljana, "Graphene oxide size and structure pro-oxidant and antioxidant activity and photoinduced cytotoxicity relation on three cancer cell lines" in Journal of Photochemistry and Photobiology B: Biology, 200 (2019):111647,
https://doi.org/10.1016/j.jphotobiol.2019.111647 . .