TY  - JOUR
AU  - Huskić, Miroslav
AU  - Kepić, Dejan
AU  - Kleut, Duška
AU  - Mozetič, Miran
AU  - Vesel, Alenka
AU  - Anžlovar, Alojz
AU  - Bajuk Bogdanović, Danica
AU  - Jovanović, Svetlana
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12874
AB  - The present study focuses on correlations between three parameters: (1) graphite particle
size, (2) the ratio of graphite to oxidizing agent (KMnO4
), and (3) the ratio of graphite to acid
(H2SO4 and H3PO4
), with the reaction yield, structure, and properties of graphene oxide (GO). The
correlations are a challenge, as these three parameters can hardly be separated from each other due to
the variations in the viscosity of the system. The larger the graphite particles, the higher the viscosity
of GO. Decreasing the ratio of graphite to KMnO4
from 1:4 to 1:6 generally leads to a higher degree
of oxidation and a higher reaction yield. However, the differences are very small. Increasing the
graphite-to-acid-volume ratio from 1 g/60 mL to 1 g/80 mL, except for the smallest particles, reduced
the degree of oxidation and slightly reduced the reaction yield. However, the reaction yield mainly
depends on the extent of purification of GO by water, not on the reaction conditions. The large
differences in the thermal decomposition of GO are mainly due to the bulk particle size and less to
other parameters
T2  - Nanomaterials
T1  - The Influence of Reaction Conditions on the Properties of Graphene Oxide
VL  - 14
IS  - 3
SP  - 281
DO  - 10.3390/nano14030281
ER  - 

@article{
author = "Huskić, Miroslav and Kepić, Dejan and Kleut, Duška and Mozetič, Miran and Vesel, Alenka and Anžlovar, Alojz and Bajuk Bogdanović, Danica and Jovanović, Svetlana",
year = "2024",
abstract = "The present study focuses on correlations between three parameters: (1) graphite particle
size, (2) the ratio of graphite to oxidizing agent (KMnO4
), and (3) the ratio of graphite to acid
(H2SO4 and H3PO4
), with the reaction yield, structure, and properties of graphene oxide (GO). The
correlations are a challenge, as these three parameters can hardly be separated from each other due to
the variations in the viscosity of the system. The larger the graphite particles, the higher the viscosity
of GO. Decreasing the ratio of graphite to KMnO4
from 1:4 to 1:6 generally leads to a higher degree
of oxidation and a higher reaction yield. However, the differences are very small. Increasing the
graphite-to-acid-volume ratio from 1 g/60 mL to 1 g/80 mL, except for the smallest particles, reduced
the degree of oxidation and slightly reduced the reaction yield. However, the reaction yield mainly
depends on the extent of purification of GO by water, not on the reaction conditions. The large
differences in the thermal decomposition of GO are mainly due to the bulk particle size and less to
other parameters",
journal = "Nanomaterials",
title = "The Influence of Reaction Conditions on the Properties of Graphene Oxide",
volume = "14",
number = "3",
pages = "281",
doi = "10.3390/nano14030281"
}

Huskić, M., Kepić, D., Kleut, D., Mozetič, M., Vesel, A., Anžlovar, A., Bajuk Bogdanović, D.,& Jovanović, S.. (2024). The Influence of Reaction Conditions on the Properties of Graphene Oxide. in Nanomaterials, 14(3), 281.
https://doi.org/10.3390/nano14030281

Huskić M, Kepić D, Kleut D, Mozetič M, Vesel A, Anžlovar A, Bajuk Bogdanović D, Jovanović S. The Influence of Reaction Conditions on the Properties of Graphene Oxide. in Nanomaterials. 2024;14(3):281.
doi:10.3390/nano14030281 .

Huskić, Miroslav, Kepić, Dejan, Kleut, Duška, Mozetič, Miran, Vesel, Alenka, Anžlovar, Alojz, Bajuk Bogdanović, Danica, Jovanović, Svetlana, "The Influence of Reaction Conditions on the Properties of Graphene Oxide" in Nanomaterials, 14, no. 3 (2024):281,
https://doi.org/10.3390/nano14030281 . .

TY  - CONF
AU  - Jovanović, Svetlana P.
AU  - Marković, Zoran M.
AU  - Todorović Marković, Biljana M.
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12996
AB  - Graphene quantum dots (GQDs) attract huge scientific attention ever since they were discovered. They are the only 0-dimensional, water-dispersible graphene-based nanomaterial. They show (i) excellent biocompatibility; (ii) stable and tunable photoluminescence in the visible part of the spectrum resistive to photobleaching; (iii) large surface area; (iv) good solubility in water and polar organic solvents. Their astonishing properties stem from the structure: graphene in the core and a vast number of different oxygen-containing functional groups such as carboxyl, carbonyl, epoxy, hydroxyl, and lactone. Their lateral size is below 100 nm, and the height is from 0.5 to a few nm. Thanks to different oxygen groups, they have very reach chemistry; they can be easily processed, modified, and functionalized. GQDs can be modified after their synthesis using different chemical reactions, which lead to changes in oxygen content, the addition of heteroatoms, binding of target molecules. Heteroatoms can be built-in GQDs structure during the process of synthesis and usually, N, S, and P are selected. They can be produced in many different ways and starting materials and all of them are dived into two main groups: bottom-up and top-down methods. Due to a large number of diverse functional groups and high surface area, GQDs create complexes with ions, cations, biomolecules, organic molecules, etc. Thanks to this feature, GQDs are studied for the application in sensing heavy metal ions, selected anions, proteins, metabolites, hormones, enzymes, pesticides, organic colors, etc. Another exciting feature of GQDs is their ability to produce reactive oxygen species under visible light.
PB  - AIP Publishing
C3  - AIP Conference Proceedings
T1  - Graphene quantum dots - from chemistry to application in photodynamic therapy
VL  - 2924
IS  - 1
SP  - 040005
DO  - 10.1063/5.0183725
ER  - 

@conference{
author = "Jovanović, Svetlana P. and Marković, Zoran M. and Todorović Marković, Biljana M.",
year = "2024",
abstract = "Graphene quantum dots (GQDs) attract huge scientific attention ever since they were discovered. They are the only 0-dimensional, water-dispersible graphene-based nanomaterial. They show (i) excellent biocompatibility; (ii) stable and tunable photoluminescence in the visible part of the spectrum resistive to photobleaching; (iii) large surface area; (iv) good solubility in water and polar organic solvents. Their astonishing properties stem from the structure: graphene in the core and a vast number of different oxygen-containing functional groups such as carboxyl, carbonyl, epoxy, hydroxyl, and lactone. Their lateral size is below 100 nm, and the height is from 0.5 to a few nm. Thanks to different oxygen groups, they have very reach chemistry; they can be easily processed, modified, and functionalized. GQDs can be modified after their synthesis using different chemical reactions, which lead to changes in oxygen content, the addition of heteroatoms, binding of target molecules. Heteroatoms can be built-in GQDs structure during the process of synthesis and usually, N, S, and P are selected. They can be produced in many different ways and starting materials and all of them are dived into two main groups: bottom-up and top-down methods. Due to a large number of diverse functional groups and high surface area, GQDs create complexes with ions, cations, biomolecules, organic molecules, etc. Thanks to this feature, GQDs are studied for the application in sensing heavy metal ions, selected anions, proteins, metabolites, hormones, enzymes, pesticides, organic colors, etc. Another exciting feature of GQDs is their ability to produce reactive oxygen species under visible light.",
publisher = "AIP Publishing",
journal = "AIP Conference Proceedings",
title = "Graphene quantum dots - from chemistry to application in photodynamic therapy",
volume = "2924",
number = "1",
pages = "040005",
doi = "10.1063/5.0183725"
}

Jovanović, S. P., Marković, Z. M.,& Todorović Marković, B. M.. (2024). Graphene quantum dots - from chemistry to application in photodynamic therapy. in AIP Conference Proceedings
AIP Publishing., 2924(1), 040005.
https://doi.org/10.1063/5.0183725

Jovanović SP, Marković ZM, Todorović Marković BM. Graphene quantum dots - from chemistry to application in photodynamic therapy. in AIP Conference Proceedings. 2024;2924(1):040005.
doi:10.1063/5.0183725 .

Jovanović, Svetlana P., Marković, Zoran M., Todorović Marković, Biljana M., "Graphene quantum dots - from chemistry to application in photodynamic therapy" in AIP Conference Proceedings, 2924, no. 1 (2024):040005,
https://doi.org/10.1063/5.0183725 . .

TY  - JOUR
AU  - Milenković, Mila
AU  - Ciasca, Gabriele
AU  - Bonasera, Aurelio
AU  - Scopelliti, Michelangelo
AU  - Marković, Olivera
AU  - Verbić, Tatjana
AU  - Todorović Marković, Biljana
AU  - Jovanović, Svetlana
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12238
AB  - The widespread abuse of traditional antibiotics has led to a global rise in antibiotic-resistant bacteria, which give in return unprecedented health risks. Therefore, there is a large and urgent need for the development of new, smart antibacterial agents able to efficiently kill or inhibit bacterial growth. In this study, we investigated the antibacterial activity of S, N-doped Graphene Quantum Dots (GQDs) as a light-triggered antibacterial agent. Gamma irradiation was employed as a tool to achieve one-step modification of GQDs in the presence of L cysteine amino acid as a source of heteroatoms. X-ray Photoelectron Spectroscopy (XPS), nuclear magnetic resonance (NMR), and zeta potential measurements provided the necessary data to clarify the structure of modified dots and verify the introduction of both S- and N-atoms in GQDs structure, but also severe changes in the aromatic, sp2 domains. Namely, γ-irradiation caused a bonding of S atoms in 1.14 at.% mainly as thiol groups, and N in 1.81 at.% as amino groups, but sp2 contribution in GQD structure was lowered from 63.00 to 4.86 at.%, as measured in dots irradiated at a dose of 200 kGy. Fluorescence quenching measurements showed that L-cysteine-modified dots are able to bind to human serum albumin. The antibacterial activity of GQDs combined with 1 and 6 h of blue light (470 nm) irradiation was tested against 8 bacterial strains. GQD-cys-25 sample provided the best results, with minimum inhibitory concentration (MIC) as low as 125 μg/mL against S. aureus, E. faecalis, and E. coli after only 1 h of blue light exposure.
T2  - Journal of Photochemistry & Photobiology, B: Biology
T1  - Blue-light-driven photoactivity of L-cysteine-modified graphene quantum  dots and their antibacterial effects
VL  - 250
SP  - 112818
DO  - 10.1016/j.jphotobiol.2023.112818
ER  - 

@article{
author = "Milenković, Mila and Ciasca, Gabriele and Bonasera, Aurelio and Scopelliti, Michelangelo and Marković, Olivera and Verbić, Tatjana and Todorović Marković, Biljana and Jovanović, Svetlana",
year = "2024",
abstract = "The widespread abuse of traditional antibiotics has led to a global rise in antibiotic-resistant bacteria, which give in return unprecedented health risks. Therefore, there is a large and urgent need for the development of new, smart antibacterial agents able to efficiently kill or inhibit bacterial growth. In this study, we investigated the antibacterial activity of S, N-doped Graphene Quantum Dots (GQDs) as a light-triggered antibacterial agent. Gamma irradiation was employed as a tool to achieve one-step modification of GQDs in the presence of L cysteine amino acid as a source of heteroatoms. X-ray Photoelectron Spectroscopy (XPS), nuclear magnetic resonance (NMR), and zeta potential measurements provided the necessary data to clarify the structure of modified dots and verify the introduction of both S- and N-atoms in GQDs structure, but also severe changes in the aromatic, sp2 domains. Namely, γ-irradiation caused a bonding of S atoms in 1.14 at.% mainly as thiol groups, and N in 1.81 at.% as amino groups, but sp2 contribution in GQD structure was lowered from 63.00 to 4.86 at.%, as measured in dots irradiated at a dose of 200 kGy. Fluorescence quenching measurements showed that L-cysteine-modified dots are able to bind to human serum albumin. The antibacterial activity of GQDs combined with 1 and 6 h of blue light (470 nm) irradiation was tested against 8 bacterial strains. GQD-cys-25 sample provided the best results, with minimum inhibitory concentration (MIC) as low as 125 μg/mL against S. aureus, E. faecalis, and E. coli after only 1 h of blue light exposure.",
journal = "Journal of Photochemistry & Photobiology, B: Biology",
title = "Blue-light-driven photoactivity of L-cysteine-modified graphene quantum  dots and their antibacterial effects",
volume = "250",
pages = "112818",
doi = "10.1016/j.jphotobiol.2023.112818"
}

Milenković, M., Ciasca, G., Bonasera, A., Scopelliti, M., Marković, O., Verbić, T., Todorović Marković, B.,& Jovanović, S.. (2024). Blue-light-driven photoactivity of L-cysteine-modified graphene quantum  dots and their antibacterial effects. in Journal of Photochemistry & Photobiology, B: Biology, 250, 112818.
https://doi.org/10.1016/j.jphotobiol.2023.112818

Milenković M, Ciasca G, Bonasera A, Scopelliti M, Marković O, Verbić T, Todorović Marković B, Jovanović S. Blue-light-driven photoactivity of L-cysteine-modified graphene quantum  dots and their antibacterial effects. in Journal of Photochemistry & Photobiology, B: Biology. 2024;250:112818.
doi:10.1016/j.jphotobiol.2023.112818 .

Milenković, Mila, Ciasca, Gabriele, Bonasera, Aurelio, Scopelliti, Michelangelo, Marković, Olivera, Verbić, Tatjana, Todorović Marković, Biljana, Jovanović, Svetlana, "Blue-light-driven photoactivity of L-cysteine-modified graphene quantum  dots and their antibacterial effects" in Journal of Photochemistry & Photobiology, B: Biology, 250 (2024):112818,
https://doi.org/10.1016/j.jphotobiol.2023.112818 . .

TY  - CONF
AU  - Kleut, Duška
AU  - Milenković, Mila
AU  - Von Kleist-Retzow, Fabian
AU  - Sebbache, Mohamed
AU  - Haddadi, Kamel
AU  - Jovanović, Svetlana
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12212
AB  - With the growing penetration of microwave applications in modern society, exposure to electromagnetic waves (EMWs) may become an important public health problem. In addition, the coexistence of high frequency devices and systems induce electromagnetic Interferences (EMIs) leading to electromagnetic pertubations and lifetime reduction. consequently, shielding materials capable of blocking EMWs are highly needed. In this paper, composite materials based on graphene oxides and silver nanowires were studied as potential EMW shielding materials. Composites were obtained from graphene oxide (GO) with sheet size between 150 and 2000 nm and thicknesses of flakes in range 2–5 nm. Average thickness of free-standing films were around 14.8 μm . We studied the ratio between these nanomaterials to modulate shielding efficiency in a broad microwave frequency range up to 18 GHz. The shielding efficiency of around 6.5 dB was measured for the r-GO free-standing film.
PB  - IEEE : Institute of Electrical and Electronics Engineers
C3  - MARSS 2023 : 6th International Conference on Manipulation, Automation and Robotics at Small Scales : Proceedings
T1  - Microwave Electromagnetic Shielding with Free-Standing Composites Based on Graphene Oxide and Silver Nanowires
SP  - 1
EP  - 6
DO  - 10.1109/MARSS58567.2023.10294133
ER  - 

@conference{
author = "Kleut, Duška and Milenković, Mila and Von Kleist-Retzow, Fabian and Sebbache, Mohamed and Haddadi, Kamel and Jovanović, Svetlana",
year = "2023",
abstract = "With the growing penetration of microwave applications in modern society, exposure to electromagnetic waves (EMWs) may become an important public health problem. In addition, the coexistence of high frequency devices and systems induce electromagnetic Interferences (EMIs) leading to electromagnetic pertubations and lifetime reduction. consequently, shielding materials capable of blocking EMWs are highly needed. In this paper, composite materials based on graphene oxides and silver nanowires were studied as potential EMW shielding materials. Composites were obtained from graphene oxide (GO) with sheet size between 150 and 2000 nm and thicknesses of flakes in range 2–5 nm. Average thickness of free-standing films were around 14.8 μm . We studied the ratio between these nanomaterials to modulate shielding efficiency in a broad microwave frequency range up to 18 GHz. The shielding efficiency of around 6.5 dB was measured for the r-GO free-standing film.",
publisher = "IEEE : Institute of Electrical and Electronics Engineers",
journal = "MARSS 2023 : 6th International Conference on Manipulation, Automation and Robotics at Small Scales : Proceedings",
title = "Microwave Electromagnetic Shielding with Free-Standing Composites Based on Graphene Oxide and Silver Nanowires",
pages = "1-6",
doi = "10.1109/MARSS58567.2023.10294133"
}

Kleut, D., Milenković, M., Von Kleist-Retzow, F., Sebbache, M., Haddadi, K.,& Jovanović, S.. (2023). Microwave Electromagnetic Shielding with Free-Standing Composites Based on Graphene Oxide and Silver Nanowires. in MARSS 2023 : 6th International Conference on Manipulation, Automation and Robotics at Small Scales : Proceedings
IEEE : Institute of Electrical and Electronics Engineers., 1-6.
https://doi.org/10.1109/MARSS58567.2023.10294133

Kleut D, Milenković M, Von Kleist-Retzow F, Sebbache M, Haddadi K, Jovanović S. Microwave Electromagnetic Shielding with Free-Standing Composites Based on Graphene Oxide and Silver Nanowires. in MARSS 2023 : 6th International Conference on Manipulation, Automation and Robotics at Small Scales : Proceedings. 2023;:1-6.
doi:10.1109/MARSS58567.2023.10294133 .

Kleut, Duška, Milenković, Mila, Von Kleist-Retzow, Fabian, Sebbache, Mohamed, Haddadi, Kamel, Jovanović, Svetlana, "Microwave Electromagnetic Shielding with Free-Standing Composites Based on Graphene Oxide and Silver Nanowires" in MARSS 2023 : 6th International Conference on Manipulation, Automation and Robotics at Small Scales : Proceedings (2023):1-6,
https://doi.org/10.1109/MARSS58567.2023.10294133 . .

TY  - JOUR
AU  - Jovanović, Svetlana P.
AU  - Marković, Zoran M.
AU  - Budimir, Milica
AU  - Prekodravac, Jovana
AU  - Zmejkoski, Danica
AU  - Kepić, Dejan
AU  - Bonasera, Aurelio
AU  - Todorović-Marković, Biljana
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10926
AB  - The large number of deaths induced by carcinoma and infections indicates that the need for new, better, targeted therapy is higher than ever. Apart from classical treatments and medication, photodynamic therapy (PDT) is one of the possible approaches to cure these clinical conditions. This strategy offers several advantages, such as lower toxicity, selective treatment, faster recovery time, avoidance of systemic toxic effects, and others. Unfortunately, there is a small number of agents that are approved for usage in clinical PDT. Novel, efficient, biocompatible PDT agents are, thus, highly desired. One of the most promising candidates is represented by the broad family of carbon-based quantum dots, such as graphene quantum dots (GQDs), carbon quantum dots (CQDs), carbon nanodots (CNDs), and carbonized polymer dots (CPDs). In this review paper, these new smart nanomaterials are discussed as potential PDT agents, detailing their toxicity in the dark, and when they are exposed to light, as well as their effects on carcinoma and bacterial cells. The photoinduced effects of carbon-based quantum dots on bacteria and viruses are particularly interesting, since dots usually generate several highly toxic reactive oxygen species under blue light. These species are acting as bombs on pathogen cells, causing various devastating and toxic effects on those targets.
T2  - Pharmaceutics
T1  - Lights and Dots toward Therapy—Carbon-Based Quantum Dots as New Agents for Photodynamic Therapy
VL  - 15
IS  - 4
SP  - 1170
DO  - 10.3390/pharmaceutics15041170
ER  - 

@article{
author = "Jovanović, Svetlana P. and Marković, Zoran M. and Budimir, Milica and Prekodravac, Jovana and Zmejkoski, Danica and Kepić, Dejan and Bonasera, Aurelio and Todorović-Marković, Biljana",
year = "2023",
abstract = "The large number of deaths induced by carcinoma and infections indicates that the need for new, better, targeted therapy is higher than ever. Apart from classical treatments and medication, photodynamic therapy (PDT) is one of the possible approaches to cure these clinical conditions. This strategy offers several advantages, such as lower toxicity, selective treatment, faster recovery time, avoidance of systemic toxic effects, and others. Unfortunately, there is a small number of agents that are approved for usage in clinical PDT. Novel, efficient, biocompatible PDT agents are, thus, highly desired. One of the most promising candidates is represented by the broad family of carbon-based quantum dots, such as graphene quantum dots (GQDs), carbon quantum dots (CQDs), carbon nanodots (CNDs), and carbonized polymer dots (CPDs). In this review paper, these new smart nanomaterials are discussed as potential PDT agents, detailing their toxicity in the dark, and when they are exposed to light, as well as their effects on carcinoma and bacterial cells. The photoinduced effects of carbon-based quantum dots on bacteria and viruses are particularly interesting, since dots usually generate several highly toxic reactive oxygen species under blue light. These species are acting as bombs on pathogen cells, causing various devastating and toxic effects on those targets.",
journal = "Pharmaceutics",
title = "Lights and Dots toward Therapy—Carbon-Based Quantum Dots as New Agents for Photodynamic Therapy",
volume = "15",
number = "4",
pages = "1170",
doi = "10.3390/pharmaceutics15041170"
}

Jovanović, S. P., Marković, Z. M., Budimir, M., Prekodravac, J., Zmejkoski, D., Kepić, D., Bonasera, A.,& Todorović-Marković, B.. (2023). Lights and Dots toward Therapy—Carbon-Based Quantum Dots as New Agents for Photodynamic Therapy. in Pharmaceutics, 15(4), 1170.
https://doi.org/10.3390/pharmaceutics15041170

Jovanović SP, Marković ZM, Budimir M, Prekodravac J, Zmejkoski D, Kepić D, Bonasera A, Todorović-Marković B. Lights and Dots toward Therapy—Carbon-Based Quantum Dots as New Agents for Photodynamic Therapy. in Pharmaceutics. 2023;15(4):1170.
doi:10.3390/pharmaceutics15041170 .

Jovanović, Svetlana P., Marković, Zoran M., Budimir, Milica, Prekodravac, Jovana, Zmejkoski, Danica, Kepić, Dejan, Bonasera, Aurelio, Todorović-Marković, Biljana, "Lights and Dots toward Therapy—Carbon-Based Quantum Dots as New Agents for Photodynamic Therapy" in Pharmaceutics, 15, no. 4 (2023):1170,
https://doi.org/10.3390/pharmaceutics15041170 . .

TY  - CONF
AU  - Stefanović, Anđela
AU  - Kepić, Dejan
AU  - Jovanović Vučetić, Svetlana
AU  - Haddadi, Kamel
AU  - Todorović Marković, Biljana
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12320
AB  - Silver nitrate has been exposed to low-dose (1–20 kGy) gamma irradiation in the presence of graphene-based material (graphene oxide or electrochemically exfoliated graphene) to form silver nanoparticles (Ag NPs). The successful nucleation and growth of Ag NPs, which produce the evenly covered graphene surface, are made possible by the vast surface area of those graphene-based materials as well as the presence of oxygen-containing functional groups on the surface. With a significant size distribution of 10–50 nm for graphene oxide and 10–100 nm for electrochemically exfoliated graphene, the produced Ag NPs were spherical. We also performed ElectroMagnetic Interference (EMI) shielding performance measurements of these materials. EMI shielding performance measurement revealed relatively good performance of the EEG material whereas GO material does not show EM shielding.
PB  - Belgrade : Institute of Technical Sciences of SASA
C3  - 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
T1  - Measurement of EMI shielding perfomance of graphene oxide – silver nanoparticles composites
SP  - 47
EP  - 47
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12320
ER  - 

@conference{
author = "Stefanović, Anđela and Kepić, Dejan and Jovanović Vučetić, Svetlana and Haddadi, Kamel and Todorović Marković, Biljana",
year = "2023",
abstract = "Silver nitrate has been exposed to low-dose (1–20 kGy) gamma irradiation in the presence of graphene-based material (graphene oxide or electrochemically exfoliated graphene) to form silver nanoparticles (Ag NPs). The successful nucleation and growth of Ag NPs, which produce the evenly covered graphene surface, are made possible by the vast surface area of those graphene-based materials as well as the presence of oxygen-containing functional groups on the surface. With a significant size distribution of 10–50 nm for graphene oxide and 10–100 nm for electrochemically exfoliated graphene, the produced Ag NPs were spherical. We also performed ElectroMagnetic Interference (EMI) shielding performance measurements of these materials. EMI shielding performance measurement revealed relatively good performance of the EEG material whereas GO material does not show EM shielding.",
publisher = "Belgrade : Institute of Technical Sciences of SASA",
journal = "21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts",
title = "Measurement of EMI shielding perfomance of graphene oxide – silver nanoparticles composites",
pages = "47-47",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12320"
}

Stefanović, A., Kepić, D., Jovanović Vučetić, S., Haddadi, K.,& Todorović Marković, B.. (2023). Measurement of EMI shielding perfomance of graphene oxide – silver nanoparticles composites. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
Belgrade : Institute of Technical Sciences of SASA., 47-47.
https://hdl.handle.net/21.15107/rcub_vinar_12320

Stefanović A, Kepić D, Jovanović Vučetić S, Haddadi K, Todorović Marković B. Measurement of EMI shielding perfomance of graphene oxide – silver nanoparticles composites. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts. 2023;:47-47.
https://hdl.handle.net/21.15107/rcub_vinar_12320 .

Stefanović, Anđela, Kepić, Dejan, Jovanović Vučetić, Svetlana, Haddadi, Kamel, Todorović Marković, Biljana, "Measurement of EMI shielding perfomance of graphene oxide – silver nanoparticles composites" in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts (2023):47-47,
https://hdl.handle.net/21.15107/rcub_vinar_12320 .

TY  - CONF
AU  - Dorontić, Slađana
AU  - Jovanović, Svetlana
AU  - Jovanović Vučetić, Svetlana
AU  - Todorović Marković, Biljana
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12321
AB  - Due to the exponential growth of bacterial infection as well as resistance toward most antibiotics, the development of new materials for treatment is urgently needed. In recent years, graphene quantum dots (GQDs) have been identified as promising carbon nanomaterial for eco-friendly antibacterial applications due to their optical and chemical stability, non-toxicity, and biocompatibility. One of the reported GQD’s antimicrobial mechanisms is the photo-induced production of singlet oxygen (1O2). Under light exposure, GQDs transfer the energy to molecular oxygen from the surrounding medium. Oxygen molecules transform to their excited form 1O2, which causes oxidative stress in bacterial cells and reduces their viability. In this study, pristine GQDs were produced in an easy, one-step electrochemical top-down approach using graphite electrodes as a starting material. Carboxyl groups of GQDs are modified using a carbodiimide coupling reaction catalyzed by 1-ethyl-3- (3-dimethylaminopropyl)carbodiimide (EDC), with ethylenediamine (EDA) as an amine. In the next step, these NH2 terminated dots were decorated with gold nanoparticles (AuNPs) by the same EDC coupling procedure. Abillity of GQDs-AuNP nanocomposite to generate singlet oxygen upon blue light (470 nm) was investigated by UV-Vis spectroscopy and 9,10- anthracenediylbis-(methylene)dimalonic acid (ABDA) as selective 1O2 traping agent. After 2 hours of blue light illumination, the band at 420 nm charachterisic for ABDA was completly disaperided only in the presence of the GQD-AuNPs indicating good prooxidative potential of composite. Photoinduced antibacterial effects of GQD-AuNPs were studied using minimum inhibitory concentration (MIC) test which showed great antibacterial activity against several bacterial strains.
PB  - Belgrade : Institute of Technical Sciences of SASA
C3  - 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
T1  - Plasmon induced enhancement of photoinduced antibacterial activity of graphene quantum dots
SP  - 48
EP  - 48
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12321
ER  - 

@conference{
author = "Dorontić, Slađana and Jovanović, Svetlana and Jovanović Vučetić, Svetlana and Todorović Marković, Biljana",
year = "2023",
abstract = "Due to the exponential growth of bacterial infection as well as resistance toward most antibiotics, the development of new materials for treatment is urgently needed. In recent years, graphene quantum dots (GQDs) have been identified as promising carbon nanomaterial for eco-friendly antibacterial applications due to their optical and chemical stability, non-toxicity, and biocompatibility. One of the reported GQD’s antimicrobial mechanisms is the photo-induced production of singlet oxygen (1O2). Under light exposure, GQDs transfer the energy to molecular oxygen from the surrounding medium. Oxygen molecules transform to their excited form 1O2, which causes oxidative stress in bacterial cells and reduces their viability. In this study, pristine GQDs were produced in an easy, one-step electrochemical top-down approach using graphite electrodes as a starting material. Carboxyl groups of GQDs are modified using a carbodiimide coupling reaction catalyzed by 1-ethyl-3- (3-dimethylaminopropyl)carbodiimide (EDC), with ethylenediamine (EDA) as an amine. In the next step, these NH2 terminated dots were decorated with gold nanoparticles (AuNPs) by the same EDC coupling procedure. Abillity of GQDs-AuNP nanocomposite to generate singlet oxygen upon blue light (470 nm) was investigated by UV-Vis spectroscopy and 9,10- anthracenediylbis-(methylene)dimalonic acid (ABDA) as selective 1O2 traping agent. After 2 hours of blue light illumination, the band at 420 nm charachterisic for ABDA was completly disaperided only in the presence of the GQD-AuNPs indicating good prooxidative potential of composite. Photoinduced antibacterial effects of GQD-AuNPs were studied using minimum inhibitory concentration (MIC) test which showed great antibacterial activity against several bacterial strains.",
publisher = "Belgrade : Institute of Technical Sciences of SASA",
journal = "21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts",
title = "Plasmon induced enhancement of photoinduced antibacterial activity of graphene quantum dots",
pages = "48-48",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12321"
}

Dorontić, S., Jovanović, S., Jovanović Vučetić, S.,& Todorović Marković, B.. (2023). Plasmon induced enhancement of photoinduced antibacterial activity of graphene quantum dots. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
Belgrade : Institute of Technical Sciences of SASA., 48-48.
https://hdl.handle.net/21.15107/rcub_vinar_12321

Dorontić S, Jovanović S, Jovanović Vučetić S, Todorović Marković B. Plasmon induced enhancement of photoinduced antibacterial activity of graphene quantum dots. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts. 2023;:48-48.
https://hdl.handle.net/21.15107/rcub_vinar_12321 .

Dorontić, Slađana, Jovanović, Svetlana, Jovanović Vučetić, Svetlana, Todorović Marković, Biljana, "Plasmon induced enhancement of photoinduced antibacterial activity of graphene quantum dots" in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts (2023):48-48,
https://hdl.handle.net/21.15107/rcub_vinar_12321 .

TY  - CONF
AU  - Milenković, Mila
AU  - Dorontić, Slađana
AU  - Todorović Marković, Biljana
AU  - Jovanović, Svetlana
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12322
AB  - Considering the rising concern of antibiotic resistance, developing advanced antibacterial solutions is highly needed. The ability of graphene quantum dots (GQDs) to generate reactive oxygen species (ROS) upon light exposure made them promising candidates as agents in photodynamic therapy for combatting infections, including antibiotic-resistant strains. GQDs show versatile chemical, physical, and biological properties such as high fluorescent activity, resistance to photo-bleaching, low toxicity, excellent solubility, and biocompatibility. This research focused on exploring the ability of GQDs to produce singlet oxygen under blue light exposure. We used two singlet oxygen probes, 9,10-anthracenediylbis(methylene) dimalonic acid and 1,3-diphenylisobenzofuran to study photoinduced production radicals from several GQDs. To tune the ability of GQDs to generate ROS, we used gamma irradiation in two different media, the presence of L-cysteine and cyclopentanone. The results showed improvements in singlet oxygen production in both cases. However, the modification conducted with cyclopentanol showed notably higher efficacy in promoting singlet oxygen production. This research demonstrates the increasing significance of GQDs in discovering new methods to combat bacteria. The modification of GQDs with gamma irradiation leads to increased production of singlet oxygen enhancing the effectiveness of photodynamic therapy for treating infections.
PB  - Belgrade : Institute of Technical Sciences of SASA
C3  - 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
T1  - Innovative modifications of graphene quantum dots for improved photodynamic therapy in antibacterial treatment
SP  - 49
EP  - 49
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12322
ER  - 

@conference{
author = "Milenković, Mila and Dorontić, Slađana and Todorović Marković, Biljana and Jovanović, Svetlana",
year = "2023",
abstract = "Considering the rising concern of antibiotic resistance, developing advanced antibacterial solutions is highly needed. The ability of graphene quantum dots (GQDs) to generate reactive oxygen species (ROS) upon light exposure made them promising candidates as agents in photodynamic therapy for combatting infections, including antibiotic-resistant strains. GQDs show versatile chemical, physical, and biological properties such as high fluorescent activity, resistance to photo-bleaching, low toxicity, excellent solubility, and biocompatibility. This research focused on exploring the ability of GQDs to produce singlet oxygen under blue light exposure. We used two singlet oxygen probes, 9,10-anthracenediylbis(methylene) dimalonic acid and 1,3-diphenylisobenzofuran to study photoinduced production radicals from several GQDs. To tune the ability of GQDs to generate ROS, we used gamma irradiation in two different media, the presence of L-cysteine and cyclopentanone. The results showed improvements in singlet oxygen production in both cases. However, the modification conducted with cyclopentanol showed notably higher efficacy in promoting singlet oxygen production. This research demonstrates the increasing significance of GQDs in discovering new methods to combat bacteria. The modification of GQDs with gamma irradiation leads to increased production of singlet oxygen enhancing the effectiveness of photodynamic therapy for treating infections.",
publisher = "Belgrade : Institute of Technical Sciences of SASA",
journal = "21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts",
title = "Innovative modifications of graphene quantum dots for improved photodynamic therapy in antibacterial treatment",
pages = "49-49",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12322"
}

Milenković, M., Dorontić, S., Todorović Marković, B.,& Jovanović, S.. (2023). Innovative modifications of graphene quantum dots for improved photodynamic therapy in antibacterial treatment. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts
Belgrade : Institute of Technical Sciences of SASA., 49-49.
https://hdl.handle.net/21.15107/rcub_vinar_12322

Milenković M, Dorontić S, Todorović Marković B, Jovanović S. Innovative modifications of graphene quantum dots for improved photodynamic therapy in antibacterial treatment. in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts. 2023;:49-49.
https://hdl.handle.net/21.15107/rcub_vinar_12322 .

Milenković, Mila, Dorontić, Slađana, Todorović Marković, Biljana, Jovanović, Svetlana, "Innovative modifications of graphene quantum dots for improved photodynamic therapy in antibacterial treatment" in 21st Young Researchers' Conference Materials Sciences and Engineering : program and the book of abstracts (2023):49-49,
https://hdl.handle.net/21.15107/rcub_vinar_12322 .

TY  - CONF
AU  - Dorontić, Slađana
AU  - Milivojević, Dušan
AU  - Jovanović, Svetlana P.
AU  - Todorović-Marković, Biljana
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12504
PB  - Belgrade : Serbian Chemical Society
C3  - 9th Symposium Chemistry and Environmental Protection : Book of Abstracts
T1  - Photo-induced prooxidative and antioxidative properties of gamma-irradiated graphene quantum dots
SP  - 145
EP  - 146
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12504
ER  - 

@conference{
author = "Dorontić, Slađana and Milivojević, Dušan and Jovanović, Svetlana P. and Todorović-Marković, Biljana",
year = "2023",
publisher = "Belgrade : Serbian Chemical Society",
journal = "9th Symposium Chemistry and Environmental Protection : Book of Abstracts",
title = "Photo-induced prooxidative and antioxidative properties of gamma-irradiated graphene quantum dots",
pages = "145-146",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12504"
}

Dorontić, S., Milivojević, D., Jovanović, S. P.,& Todorović-Marković, B.. (2023). Photo-induced prooxidative and antioxidative properties of gamma-irradiated graphene quantum dots. in 9th Symposium Chemistry and Environmental Protection : Book of Abstracts
Belgrade : Serbian Chemical Society., 145-146.
https://hdl.handle.net/21.15107/rcub_vinar_12504

Dorontić S, Milivojević D, Jovanović SP, Todorović-Marković B. Photo-induced prooxidative and antioxidative properties of gamma-irradiated graphene quantum dots. in 9th Symposium Chemistry and Environmental Protection : Book of Abstracts. 2023;:145-146.
https://hdl.handle.net/21.15107/rcub_vinar_12504 .

Dorontić, Slađana, Milivojević, Dušan, Jovanović, Svetlana P., Todorović-Marković, Biljana, "Photo-induced prooxidative and antioxidative properties of gamma-irradiated graphene quantum dots" in 9th Symposium Chemistry and Environmental Protection : Book of Abstracts (2023):145-146,
https://hdl.handle.net/21.15107/rcub_vinar_12504 .

TY  - CONF
AU  - Dorontić, Slađana
AU  - Jovanović, Svetlana P.
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12503
PB  - Belgrade : Serbian Chemical Society
C3  - 9th Symposium Chemistry and Environmental Protection : Book of Abstracts
T1  - Eco-friendly fabrication of graphene from apple biomass precursor
SP  - 143
EP  - 144
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12503
ER  - 

@conference{
author = "Dorontić, Slađana and Jovanović, Svetlana P.",
year = "2023",
publisher = "Belgrade : Serbian Chemical Society",
journal = "9th Symposium Chemistry and Environmental Protection : Book of Abstracts",
title = "Eco-friendly fabrication of graphene from apple biomass precursor",
pages = "143-144",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12503"
}

Dorontić, S.,& Jovanović, S. P.. (2023). Eco-friendly fabrication of graphene from apple biomass precursor. in 9th Symposium Chemistry and Environmental Protection : Book of Abstracts
Belgrade : Serbian Chemical Society., 143-144.
https://hdl.handle.net/21.15107/rcub_vinar_12503

Dorontić S, Jovanović SP. Eco-friendly fabrication of graphene from apple biomass precursor. in 9th Symposium Chemistry and Environmental Protection : Book of Abstracts. 2023;:143-144.
https://hdl.handle.net/21.15107/rcub_vinar_12503 .

Dorontić, Slađana, Jovanović, Svetlana P., "Eco-friendly fabrication of graphene from apple biomass precursor" in 9th Symposium Chemistry and Environmental Protection : Book of Abstracts (2023):143-144,
https://hdl.handle.net/21.15107/rcub_vinar_12503 .

TY  - JOUR
AU  - Jovanović, Svetlana
AU  - Huskić, Miroslav
AU  - Kepić, Dejan
AU  - Yasir, Muhammad
AU  - Haddadi, Kamel
PY  - 2023
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12607
AB  - As wireless solutions for communication, information, and sensing in modern society, electromagnetic waves (EMWs) have contributed considerably to the increase in the quality of people’s everyday lives. At the same time, EMWs produce electromagnetic pollution, issues with electromagnetic interference (EMI), and radio frequency (RF) signal leakage. These circumstances lead to high demand for efficient EMI shielding materials.  To design an EMI shielding product, a compromise must be achieved between the electromagnetic shielding efficiency, the thickness of shielding materials, durability, mechanical strength, reduced volume and weight, and elasticity. Due to its ability to block EMWs, flexibility, lightweight, and chemical resistivity, graphene has been identified as a promising candidate material for efficient EMI shielding. Herein, we reviewed the studies that investigated various graphene-based composites as potential EMI shielding materials, with a focus on the composites based on graphene and silver nanowires due to their high EMI shielding efficiency, low production price, and favorable mechanical properties.
T2  - Graphene and 2D Materials
T1  - A review on graphene and graphene composites for application in electromagnetic shielding
VL  - 8
IS  - 3-4
SP  - 59
EP  - 80
DO  - 10.1007/s41127-023-00065-3
ER  - 

@article{
author = "Jovanović, Svetlana and Huskić, Miroslav and Kepić, Dejan and Yasir, Muhammad and Haddadi, Kamel",
year = "2023",
abstract = "As wireless solutions for communication, information, and sensing in modern society, electromagnetic waves (EMWs) have contributed considerably to the increase in the quality of people’s everyday lives. At the same time, EMWs produce electromagnetic pollution, issues with electromagnetic interference (EMI), and radio frequency (RF) signal leakage. These circumstances lead to high demand for efficient EMI shielding materials.  To design an EMI shielding product, a compromise must be achieved between the electromagnetic shielding efficiency, the thickness of shielding materials, durability, mechanical strength, reduced volume and weight, and elasticity. Due to its ability to block EMWs, flexibility, lightweight, and chemical resistivity, graphene has been identified as a promising candidate material for efficient EMI shielding. Herein, we reviewed the studies that investigated various graphene-based composites as potential EMI shielding materials, with a focus on the composites based on graphene and silver nanowires due to their high EMI shielding efficiency, low production price, and favorable mechanical properties.",
journal = "Graphene and 2D Materials",
title = "A review on graphene and graphene composites for application in electromagnetic shielding",
volume = "8",
number = "3-4",
pages = "59-80",
doi = "10.1007/s41127-023-00065-3"
}

Jovanović, S., Huskić, M., Kepić, D., Yasir, M.,& Haddadi, K.. (2023). A review on graphene and graphene composites for application in electromagnetic shielding. in Graphene and 2D Materials, 8(3-4), 59-80.
https://doi.org/10.1007/s41127-023-00065-3

Jovanović S, Huskić M, Kepić D, Yasir M, Haddadi K. A review on graphene and graphene composites for application in electromagnetic shielding. in Graphene and 2D Materials. 2023;8(3-4):59-80.
doi:10.1007/s41127-023-00065-3 .

Jovanović, Svetlana, Huskić, Miroslav, Kepić, Dejan, Yasir, Muhammad, Haddadi, Kamel, "A review on graphene and graphene composites for application in electromagnetic shielding" in Graphene and 2D Materials, 8, no. 3-4 (2023):59-80,
https://doi.org/10.1007/s41127-023-00065-3 . .

TY  - JOUR
AU  - Jovanović, Svetlana P.
AU  - Bonasera, Aurelio
AU  - Dorontić, Slađana
AU  - Zmejkoski, Danica
AU  - Milivojević, Dušan
AU  - Janakiev, Tamara
AU  - Todorović-Marković, Biljana
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10633
AB  - Due to the increasing number of bacterial infections and the development of resistivity toward antibiotics, new materials and approaches for treatments must be urgently developed. The production of new materials should be ecologically friendly considering overall pollution with chemicals and economically acceptable and accessible to the wide population. Thus, the possibility of using biocompatible graphene quantum dots (GQDs) as an agent in photodynamic therapy was studied. First, dots were obtained using electrochemical cutting of graphite. In only one synthetic step using gamma irradiation, GQDs were doped with N atoms without any reagent. Obtained dots showed blue photoluminescence, with a diameter of 19–89 nm and optical band gap of 3.23–4.73 eV, featuring oxygen-containing, amino, and amide functional groups. Dots showed antioxidative activity; they quenched •OH at a concentration of 10 μg·mL−1, scavenged DPPH• radicals even at 5 μg·mL−1, and caused discoloration of KMnO4 at 30 μg·mL−1. Under light irradiation, dots were able to produce singlet oxygen, which remained stable for 10 min. Photoinduced effects by GQDs were studied on several bacterial strains (Listeria monocytogenes, Bacillus cereus, clinical strains of Streptococcus mutans, S. pyogenes, and S. sangunis, Pseudomonas aeruginosa, and one yeast strain Candida albicans) but antibacterial effects were not noticed.
T2  - Materials
T1  - Antioxidative and Photo-Induced Effects of Different Types of N-Doped Graphene Quantum Dots
VL  - 15
IS  - 19
SP  - 6525
DO  - 10.3390/ma15196525
ER  - 

@article{
author = "Jovanović, Svetlana P. and Bonasera, Aurelio and Dorontić, Slađana and Zmejkoski, Danica and Milivojević, Dušan and Janakiev, Tamara and Todorović-Marković, Biljana",
year = "2022",
abstract = "Due to the increasing number of bacterial infections and the development of resistivity toward antibiotics, new materials and approaches for treatments must be urgently developed. The production of new materials should be ecologically friendly considering overall pollution with chemicals and economically acceptable and accessible to the wide population. Thus, the possibility of using biocompatible graphene quantum dots (GQDs) as an agent in photodynamic therapy was studied. First, dots were obtained using electrochemical cutting of graphite. In only one synthetic step using gamma irradiation, GQDs were doped with N atoms without any reagent. Obtained dots showed blue photoluminescence, with a diameter of 19–89 nm and optical band gap of 3.23–4.73 eV, featuring oxygen-containing, amino, and amide functional groups. Dots showed antioxidative activity; they quenched •OH at a concentration of 10 μg·mL−1, scavenged DPPH• radicals even at 5 μg·mL−1, and caused discoloration of KMnO4 at 30 μg·mL−1. Under light irradiation, dots were able to produce singlet oxygen, which remained stable for 10 min. Photoinduced effects by GQDs were studied on several bacterial strains (Listeria monocytogenes, Bacillus cereus, clinical strains of Streptococcus mutans, S. pyogenes, and S. sangunis, Pseudomonas aeruginosa, and one yeast strain Candida albicans) but antibacterial effects were not noticed.",
journal = "Materials",
title = "Antioxidative and Photo-Induced Effects of Different Types of N-Doped Graphene Quantum Dots",
volume = "15",
number = "19",
pages = "6525",
doi = "10.3390/ma15196525"
}

Jovanović, S. P., Bonasera, A., Dorontić, S., Zmejkoski, D., Milivojević, D., Janakiev, T.,& Todorović-Marković, B.. (2022). Antioxidative and Photo-Induced Effects of Different Types of N-Doped Graphene Quantum Dots. in Materials, 15(19), 6525.
https://doi.org/10.3390/ma15196525

Jovanović SP, Bonasera A, Dorontić S, Zmejkoski D, Milivojević D, Janakiev T, Todorović-Marković B. Antioxidative and Photo-Induced Effects of Different Types of N-Doped Graphene Quantum Dots. in Materials. 2022;15(19):6525.
doi:10.3390/ma15196525 .

Jovanović, Svetlana P., Bonasera, Aurelio, Dorontić, Slađana, Zmejkoski, Danica, Milivojević, Dušan, Janakiev, Tamara, Todorović-Marković, Biljana, "Antioxidative and Photo-Induced Effects of Different Types of N-Doped Graphene Quantum Dots" in Materials, 15, no. 19 (2022):6525,
https://doi.org/10.3390/ma15196525 . .

TY  - CONF
AU  - Dorontić, Slađana
AU  - Sredojević, Dušan
AU  - Bajuk-Bogdanović, Danica
AU  - Jovanović, Svetlana P.
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12498
AB  - The increasing presence of pesticides and heavy metals in the environment and their negative impact on human, animal, and plant health, demand green, low-cost, and simple methods for their monitoring. Due to photoluminescence (PL) in the visible part of the spectrum, biocompatibility, and ecological acceptability, graphene quantum dots (GQDs) are at the center of attention in the field of optical sensing. GQDs show great potential as PL sensors for Pd(II) ions and insecticide carbofuran. In this work, FTIR spectroscopy and Density Functional Theory (DFT) calculation were used to resolve the mechanism of PL change in the presence of these analytes.
PB  - Szeged : University of Szeged
C3  - 28th International Symposium on Analytical and Environmental Problems : Proceedings; November 14-15, 2022; Szeged, Hungary
T1  - The Mechanism Behind Pd(II) and Carbofuran-Induced Change of Graphene Quantum Dots Photoluminescence Intensity
SP  - 124
EP  - 128
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12498
ER  - 

@conference{
author = "Dorontić, Slađana and Sredojević, Dušan and Bajuk-Bogdanović, Danica and Jovanović, Svetlana P.",
year = "2022",
abstract = "The increasing presence of pesticides and heavy metals in the environment and their negative impact on human, animal, and plant health, demand green, low-cost, and simple methods for their monitoring. Due to photoluminescence (PL) in the visible part of the spectrum, biocompatibility, and ecological acceptability, graphene quantum dots (GQDs) are at the center of attention in the field of optical sensing. GQDs show great potential as PL sensors for Pd(II) ions and insecticide carbofuran. In this work, FTIR spectroscopy and Density Functional Theory (DFT) calculation were used to resolve the mechanism of PL change in the presence of these analytes.",
publisher = "Szeged : University of Szeged",
journal = "28th International Symposium on Analytical and Environmental Problems : Proceedings; November 14-15, 2022; Szeged, Hungary",
title = "The Mechanism Behind Pd(II) and Carbofuran-Induced Change of Graphene Quantum Dots Photoluminescence Intensity",
pages = "124-128",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12498"
}

Dorontić, S., Sredojević, D., Bajuk-Bogdanović, D.,& Jovanović, S. P.. (2022). The Mechanism Behind Pd(II) and Carbofuran-Induced Change of Graphene Quantum Dots Photoluminescence Intensity. in 28th International Symposium on Analytical and Environmental Problems : Proceedings; November 14-15, 2022; Szeged, Hungary
Szeged : University of Szeged., 124-128.
https://hdl.handle.net/21.15107/rcub_vinar_12498

Dorontić S, Sredojević D, Bajuk-Bogdanović D, Jovanović SP. The Mechanism Behind Pd(II) and Carbofuran-Induced Change of Graphene Quantum Dots Photoluminescence Intensity. in 28th International Symposium on Analytical and Environmental Problems : Proceedings; November 14-15, 2022; Szeged, Hungary. 2022;:124-128.
https://hdl.handle.net/21.15107/rcub_vinar_12498 .

Dorontić, Slađana, Sredojević, Dušan, Bajuk-Bogdanović, Danica, Jovanović, Svetlana P., "The Mechanism Behind Pd(II) and Carbofuran-Induced Change of Graphene Quantum Dots Photoluminescence Intensity" in 28th International Symposium on Analytical and Environmental Problems : Proceedings; November 14-15, 2022; Szeged, Hungary (2022):124-128,
https://hdl.handle.net/21.15107/rcub_vinar_12498 .

TY  - JOUR
AU  - Dorontić, Slađana
AU  - Bonasera, Aurelio
AU  - Scopelliti, Michelangelo
AU  - Marković, Olivera
AU  - Bajuk Bogdanović, Danica
AU  - Ciasca, Gabriele
AU  - Romanò, Sabrina
AU  - Dimkić, Ivica
AU  - Budimir, Milica
AU  - Marinković, Dragana
AU  - Jovanović, Svetlana P.
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10406
AB  - Structural modification of different carbon-based nanomaterials is often necessary toimprove their morphology and optical properties, particularly the incorporation of N-atoms ingraphene quantum dots (GQDs). Here, a clean, simple, one-step, and eco-friendly method forN-doping of GQDs using gamma irradiation is reported. GQDs were irradiated in the presenceof the different ethylenediamine (EDA) amounts (1 g, 5 g, and 10 g) and the highest % of N wasdetected in the presence of 10 g. N-doped GQDs emitted strong, blue photoluminescence (PL).Photoluminescence quantum yield was increased from 1.45, as obtained for non-irradiated dots,to 7.24% for those irradiated in the presence of 1 g of EDA. Modified GQDs were investigated asa PL probe for the detection of insecticide Carbofuran (2,2-Dimethyl-2,3-dihydro-1-benzofuran-7-yl methylcarbamate) and herbicide Amitrole (3-amino-1,2,4-triazole). The limit of detection was5.4 µmol L−1for Carbofuran. For the first time, Amitrole was detected by GQDs in a turn-off/turn-onmechanism using Pd(II) ions as a quenching agent. First, Pd(II) ions were quenched (turn-off) PLof GQDs, while after Amitrole addition, PL was recovered linearly with Amitrole concentration(turn-on). LOD was 2.03 µmol L−1. These results suggest that modified GQDs can be used as anefficient new material for Carbofuran and Amitrole detection. Furthermore, the phototoxicity of dotswas investigated on both Gram-positive and Gram-negative bacterial strains. When bacterial cellswere exposed to different GQD concentrations and illuminated with light of 470 nm wavelength, thetoxic effects were not observed.
T2  - Nanomaterials
T1  - Gamma-ray-induced structural transformation of GQDs towards the improvement of their optical properties, monitoring of selected toxic compounds, and photo-induced effect on bacterial strains
VL  - 12
SP  - 2714
DO  - 10.3390/nano12152714
ER  - 

@article{
author = "Dorontić, Slađana and Bonasera, Aurelio and Scopelliti, Michelangelo and Marković, Olivera and Bajuk Bogdanović, Danica and Ciasca, Gabriele and Romanò, Sabrina and Dimkić, Ivica and Budimir, Milica and Marinković, Dragana and Jovanović, Svetlana P.",
year = "2022",
abstract = "Structural modification of different carbon-based nanomaterials is often necessary toimprove their morphology and optical properties, particularly the incorporation of N-atoms ingraphene quantum dots (GQDs). Here, a clean, simple, one-step, and eco-friendly method forN-doping of GQDs using gamma irradiation is reported. GQDs were irradiated in the presenceof the different ethylenediamine (EDA) amounts (1 g, 5 g, and 10 g) and the highest % of N wasdetected in the presence of 10 g. N-doped GQDs emitted strong, blue photoluminescence (PL).Photoluminescence quantum yield was increased from 1.45, as obtained for non-irradiated dots,to 7.24% for those irradiated in the presence of 1 g of EDA. Modified GQDs were investigated asa PL probe for the detection of insecticide Carbofuran (2,2-Dimethyl-2,3-dihydro-1-benzofuran-7-yl methylcarbamate) and herbicide Amitrole (3-amino-1,2,4-triazole). The limit of detection was5.4 µmol L−1for Carbofuran. For the first time, Amitrole was detected by GQDs in a turn-off/turn-onmechanism using Pd(II) ions as a quenching agent. First, Pd(II) ions were quenched (turn-off) PLof GQDs, while after Amitrole addition, PL was recovered linearly with Amitrole concentration(turn-on). LOD was 2.03 µmol L−1. These results suggest that modified GQDs can be used as anefficient new material for Carbofuran and Amitrole detection. Furthermore, the phototoxicity of dotswas investigated on both Gram-positive and Gram-negative bacterial strains. When bacterial cellswere exposed to different GQD concentrations and illuminated with light of 470 nm wavelength, thetoxic effects were not observed.",
journal = "Nanomaterials",
title = "Gamma-ray-induced structural transformation of GQDs towards the improvement of their optical properties, monitoring of selected toxic compounds, and photo-induced effect on bacterial strains",
volume = "12",
pages = "2714",
doi = "10.3390/nano12152714"
}

Dorontić, S., Bonasera, A., Scopelliti, M., Marković, O., Bajuk Bogdanović, D., Ciasca, G., Romanò, S., Dimkić, I., Budimir, M., Marinković, D.,& Jovanović, S. P.. (2022). Gamma-ray-induced structural transformation of GQDs towards the improvement of their optical properties, monitoring of selected toxic compounds, and photo-induced effect on bacterial strains. in Nanomaterials, 12, 2714.
https://doi.org/10.3390/nano12152714

Dorontić S, Bonasera A, Scopelliti M, Marković O, Bajuk Bogdanović D, Ciasca G, Romanò S, Dimkić I, Budimir M, Marinković D, Jovanović SP. Gamma-ray-induced structural transformation of GQDs towards the improvement of their optical properties, monitoring of selected toxic compounds, and photo-induced effect on bacterial strains. in Nanomaterials. 2022;12:2714.
doi:10.3390/nano12152714 .

Dorontić, Slađana, Bonasera, Aurelio, Scopelliti, Michelangelo, Marković, Olivera, Bajuk Bogdanović, Danica, Ciasca, Gabriele, Romanò, Sabrina, Dimkić, Ivica, Budimir, Milica, Marinković, Dragana, Jovanović, Svetlana P., "Gamma-ray-induced structural transformation of GQDs towards the improvement of their optical properties, monitoring of selected toxic compounds, and photo-induced effect on bacterial strains" in Nanomaterials, 12 (2022):2714,
https://doi.org/10.3390/nano12152714 . .

TY  - JOUR
AU  - Mišović, Aleksandra
AU  - Bajuk-Bogdanović, Danica V.
AU  - Kepić, Dejan
AU  - Pavlović, Vladimir B.
AU  - Huskić, Miroslav
AU  - Hasheminejad, Navid
AU  - Vuye, Cedric
AU  - Zorić, Nemanja
AU  - Jovanović, Svetlana P.
PY  - 2022
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10078
AB  - The need for stable, chemical resistant and conductive materials is on the rise in recent times. Graphene shows promising electrical conductivity and chemical stability, but the production of a continual, conductive layer is limited and expensive. Silver nanowires (AgNWs) are both conducive and economically viable, but they are sensitive to water and oxygen. In this study, graphene oxide (GO) and AgNWs were synthesized and combined in different mass ratios (3:1, 2.5:1.5, and 1:1) to obtain chemically stable composites with improved electrical properties. Composites were reduced using ascorbic acid. With the increase of AgNWs to GO mass ratio, the surface of the free-standing composite film improved: the root mean square roughness was lowered from 376 nm for GO to 168 nm for the composite with the mass ratio of GO:AgNWs 1:1, while the sheet resistance was lowered from 146 × 106 Ω/□ to 4 Ω/□. For the first time, the effects of gamma irradiation on the structure of the composites were studied. Doses of 15, 25, and 35 kGy were applied.
T2  - Synthetic Metals
T1  - Properties of free-standing graphene oxide/silver nanowires films and effects of chemical reduction and gamma irradiation
VL  - 283
SP  - 116980
DO  - 10.1016/j.synthmet.2021.116980
ER  - 

@article{
author = "Mišović, Aleksandra and Bajuk-Bogdanović, Danica V. and Kepić, Dejan and Pavlović, Vladimir B. and Huskić, Miroslav and Hasheminejad, Navid and Vuye, Cedric and Zorić, Nemanja and Jovanović, Svetlana P.",
year = "2022",
abstract = "The need for stable, chemical resistant and conductive materials is on the rise in recent times. Graphene shows promising electrical conductivity and chemical stability, but the production of a continual, conductive layer is limited and expensive. Silver nanowires (AgNWs) are both conducive and economically viable, but they are sensitive to water and oxygen. In this study, graphene oxide (GO) and AgNWs were synthesized and combined in different mass ratios (3:1, 2.5:1.5, and 1:1) to obtain chemically stable composites with improved electrical properties. Composites were reduced using ascorbic acid. With the increase of AgNWs to GO mass ratio, the surface of the free-standing composite film improved: the root mean square roughness was lowered from 376 nm for GO to 168 nm for the composite with the mass ratio of GO:AgNWs 1:1, while the sheet resistance was lowered from 146 × 106 Ω/□ to 4 Ω/□. For the first time, the effects of gamma irradiation on the structure of the composites were studied. Doses of 15, 25, and 35 kGy were applied.",
journal = "Synthetic Metals",
title = "Properties of free-standing graphene oxide/silver nanowires films and effects of chemical reduction and gamma irradiation",
volume = "283",
pages = "116980",
doi = "10.1016/j.synthmet.2021.116980"
}

Mišović, A., Bajuk-Bogdanović, D. V., Kepić, D., Pavlović, V. B., Huskić, M., Hasheminejad, N., Vuye, C., Zorić, N.,& Jovanović, S. P.. (2022). Properties of free-standing graphene oxide/silver nanowires films and effects of chemical reduction and gamma irradiation. in Synthetic Metals, 283, 116980.
https://doi.org/10.1016/j.synthmet.2021.116980

Mišović A, Bajuk-Bogdanović DV, Kepić D, Pavlović VB, Huskić M, Hasheminejad N, Vuye C, Zorić N, Jovanović SP. Properties of free-standing graphene oxide/silver nanowires films and effects of chemical reduction and gamma irradiation. in Synthetic Metals. 2022;283:116980.
doi:10.1016/j.synthmet.2021.116980 .

Mišović, Aleksandra, Bajuk-Bogdanović, Danica V., Kepić, Dejan, Pavlović, Vladimir B., Huskić, Miroslav, Hasheminejad, Navid, Vuye, Cedric, Zorić, Nemanja, Jovanović, Svetlana P., "Properties of free-standing graphene oxide/silver nanowires films and effects of chemical reduction and gamma irradiation" in Synthetic Metals, 283 (2022):116980,
https://doi.org/10.1016/j.synthmet.2021.116980 . .

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  - Krunić, Matija
AU  - Ristić, Biljana
AU  - Bošnjak, Mihajlo
AU  - Paunović, Verica
AU  - Tovilović-Kovačević, Gordana
AU  - Zogović, Nevena
AU  - Mirčić, Aleksandar
AU  - Marković, Zoran
AU  - Todorović-Marković, Biljana
AU  - Jovanović, Svetlana P.
AU  - Kleut, Duška
AU  - Mojović, Miloš
AU  - Nakarada, Đura
AU  - Marković, Olivera
AU  - Vuković, Irena
AU  - Harhaji-Trajković, Ljubica
AU  - Trajković, Vladimir S.
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9980
AB  - We investigated the ability of graphene quantum dot (GQD) nanoparticles to protect SH-SY5Y human neuroblastoma cells from oxidative/nitrosative stress induced by iron-nitrosyl complex sodium nitroprusside (SNP).GQD reduced SNP cytotoxicity by preventing mitochondrial depolarization, caspase-2 activation, and subsequent apoptotic death. Although GQD diminished the levels of nitric oxide (NO) in SNP-exposed cells, NO scavengers displayed only a slight protective effect, suggesting that NO quenching was not the main protective mechanism of GQD. GQD also reduced SNP-triggered increase in the intracellular levels of hydroxyl radical (•OH), superoxide anion (O2•- ), and lipid peroxidation. Nonselective antioxidants, •OH scavenging, and iron chelators, but not superoxide dismutase, mimicked GQD cytoprotective activity, indicating that GQD protect cells by neutralizing •OH generated in the presence of SNP-released iron. Cellular internalization of GQD was required for optimal protection, since a removal of extracellular GQD by extensive washing only partly diminished their protective effect. Moreover, GQD cooperated with SNP to induce autophagy, as confirmed by the inhibition of autophagylimiting Akt/PRAS40/mTOR signaling and increase in autophagy gene transcription, protein levels of proautophagic beclin-1 and LC3-II, formation of autophagic vesicles, and degradation of autophagic target p62. The antioxidant activity of GQD was not involved in autophagy induction, as antioxidants N-acetylcysteine and dimethyl sulfoxide failed to stimulate autophagy in SNP-exposed cells. Pharmacological inhibitors of early (wortmannin, 3-methyladenine) or late stages of autophagy (NH4Cl) efficiently reduced the protective effect of GQD. Therefore, the ability of GQD to prevent the in vitro neurotoxicity of SNP depends on both •OH/NO scavenging and induction of cytoprotective autophagy.
T2  - Free Radical Biology and Medicine
T1  - Graphene quantum dot antioxidant and proautophagic actions protect SH-SY5Y neuroblastoma cells from oxidative stress-mediated apoptotic death
VL  - 177
SP  - 167
EP  - 180
DO  - 10.1016/j.freeradbiomed.2021.10.025
ER  - 

@article{
author = "Krunić, Matija and Ristić, Biljana and Bošnjak, Mihajlo and Paunović, Verica and Tovilović-Kovačević, Gordana and Zogović, Nevena and Mirčić, Aleksandar and Marković, Zoran and Todorović-Marković, Biljana and Jovanović, Svetlana P. and Kleut, Duška and Mojović, Miloš and Nakarada, Đura and Marković, Olivera and Vuković, Irena and Harhaji-Trajković, Ljubica and Trajković, Vladimir S.",
year = "2021",
abstract = "We investigated the ability of graphene quantum dot (GQD) nanoparticles to protect SH-SY5Y human neuroblastoma cells from oxidative/nitrosative stress induced by iron-nitrosyl complex sodium nitroprusside (SNP).GQD reduced SNP cytotoxicity by preventing mitochondrial depolarization, caspase-2 activation, and subsequent apoptotic death. Although GQD diminished the levels of nitric oxide (NO) in SNP-exposed cells, NO scavengers displayed only a slight protective effect, suggesting that NO quenching was not the main protective mechanism of GQD. GQD also reduced SNP-triggered increase in the intracellular levels of hydroxyl radical (•OH), superoxide anion (O2•- ), and lipid peroxidation. Nonselective antioxidants, •OH scavenging, and iron chelators, but not superoxide dismutase, mimicked GQD cytoprotective activity, indicating that GQD protect cells by neutralizing •OH generated in the presence of SNP-released iron. Cellular internalization of GQD was required for optimal protection, since a removal of extracellular GQD by extensive washing only partly diminished their protective effect. Moreover, GQD cooperated with SNP to induce autophagy, as confirmed by the inhibition of autophagylimiting Akt/PRAS40/mTOR signaling and increase in autophagy gene transcription, protein levels of proautophagic beclin-1 and LC3-II, formation of autophagic vesicles, and degradation of autophagic target p62. The antioxidant activity of GQD was not involved in autophagy induction, as antioxidants N-acetylcysteine and dimethyl sulfoxide failed to stimulate autophagy in SNP-exposed cells. Pharmacological inhibitors of early (wortmannin, 3-methyladenine) or late stages of autophagy (NH4Cl) efficiently reduced the protective effect of GQD. Therefore, the ability of GQD to prevent the in vitro neurotoxicity of SNP depends on both •OH/NO scavenging and induction of cytoprotective autophagy.",
journal = "Free Radical Biology and Medicine",
title = "Graphene quantum dot antioxidant and proautophagic actions protect SH-SY5Y neuroblastoma cells from oxidative stress-mediated apoptotic death",
volume = "177",
pages = "167-180",
doi = "10.1016/j.freeradbiomed.2021.10.025"
}

Krunić, M., Ristić, B., Bošnjak, M., Paunović, V., Tovilović-Kovačević, G., Zogović, N., Mirčić, A., Marković, Z., Todorović-Marković, B., Jovanović, S. P., Kleut, D., Mojović, M., Nakarada, Đ., Marković, O., Vuković, I., Harhaji-Trajković, L.,& Trajković, V. S.. (2021). Graphene quantum dot antioxidant and proautophagic actions protect SH-SY5Y neuroblastoma cells from oxidative stress-mediated apoptotic death. in Free Radical Biology and Medicine, 177, 167-180.
https://doi.org/10.1016/j.freeradbiomed.2021.10.025

Krunić M, Ristić B, Bošnjak M, Paunović V, Tovilović-Kovačević G, Zogović N, Mirčić A, Marković Z, Todorović-Marković B, Jovanović SP, Kleut D, Mojović M, Nakarada Đ, Marković O, Vuković I, Harhaji-Trajković L, Trajković VS. Graphene quantum dot antioxidant and proautophagic actions protect SH-SY5Y neuroblastoma cells from oxidative stress-mediated apoptotic death. in Free Radical Biology and Medicine. 2021;177:167-180.
doi:10.1016/j.freeradbiomed.2021.10.025 .

Krunić, Matija, Ristić, Biljana, Bošnjak, Mihajlo, Paunović, Verica, Tovilović-Kovačević, Gordana, Zogović, Nevena, Mirčić, Aleksandar, Marković, Zoran, Todorović-Marković, Biljana, Jovanović, Svetlana P., Kleut, Duška, Mojović, Miloš, Nakarada, Đura, Marković, Olivera, Vuković, Irena, Harhaji-Trajković, Ljubica, Trajković, Vladimir S., "Graphene quantum dot antioxidant and proautophagic actions protect SH-SY5Y neuroblastoma cells from oxidative stress-mediated apoptotic death" in Free Radical Biology and Medicine, 177 (2021):167-180,
https://doi.org/10.1016/j.freeradbiomed.2021.10.025 . .

TY  - CONF
AU  - Milenković, Mila
AU  - Kleut, Duška
AU  - Jovanović, Svetlana P.
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/10907
AB  - Zero-dimensional graphene quantum dots (GQDs) are one of the most promising luminescent carbonderived nanomaterials with different oxygen-containing functional groups on their surface. They consist of one or few layers of graphene and have a lateral dimension below 100 nm. Some of their distinct and superior physical and chemical properties such as tunable photoluminescence, good biocompatibility, low toxicity, and excellent dispersibility in water, make them a promising candidate for biomedical applications [1]. With the functionalization of GQDs, it is possible to modify their surface structure by adding other functional groups thus altering photoluminescence and enhancing their other properties [2]. Gamma irradiation proved to be a simple and eco-friendly method for subsequent modification of carbon nanomaterials [3, 4]. Here, we present a simple, one-step method for functionalization of GQDs with gamma irradiation in the presence of amino acid L-cysteine as an S, N heteroatom donor and isopropyl alcohol as a radical scavenger. Water dispersion of GQDs with 1 vol% isopropyl alcohol and 2 mass% of L-cysteine was purged with Ar gas for 15 minutes and then exposed to gamma irradiation at doses: 25, 50 and 200 kGy. The optical and structural properties of obtained S, N-GQDs were investigated using Ultraviolet-visible spectroscopy (UV-Vis), Fourier-Transform Infrared spectroscopy (FTIR), Photoluminescence spectroscopy (PL), Atomic force microscopy (AFM) and Dynamic light scattering (DLS). Successful doping of S and N heteroatoms in the structure of irradiated GQDs was confirmed with FTIR analysis through detected S-H, C=S, and N-H stretching vibrations. Also, an improvement in photoluminescence quantum yield (QY) has been proved by PL measurements. The best result was achieved for the sample irradiated with a dose of 25 kGy. PL QY of this sample was 15 times higher compared to non-irradiated p-GQDs, and around 7 times higher up against other irradiated samples. Both AFM and DLS measurements were in correlation and indicated that gamma irradiation increased the layer separation and overall particle diameter of GQDs. The average diameter ranged from 25 nm up to around 30 nm for irradiated samples while the diameter of non-irradiated p-GQDs was 20 nm. The proposed one-step chemical doping provided an improvement in one of the most characteristic features of GQDs- photoluminescence, as well as in morphological properties. Due to this, the obtained S, N-GQDs have great potential for application in medicine as a bioimaging agent
PB  - Belgrade : Institute of Physics Belgrade
C3  - PHOTONICA2021 : 8th International School and Conference on Photonics and HEMMAGINERO workshop : Abstracts of Tutorial, Keynote, Invited Lectures, Progress Reports and Contributed Papers; August 23-27, 2021; Belgrade
T1  - Enhanced photoluminescence of gamma-irradiated S, N graphene quantum dots
SP  - 87
UR  - https://hdl.handle.net/21.15107/rcub_vinar_10907
ER  - 

@conference{
author = "Milenković, Mila and Kleut, Duška and Jovanović, Svetlana P.",
year = "2021",
abstract = "Zero-dimensional graphene quantum dots (GQDs) are one of the most promising luminescent carbonderived nanomaterials with different oxygen-containing functional groups on their surface. They consist of one or few layers of graphene and have a lateral dimension below 100 nm. Some of their distinct and superior physical and chemical properties such as tunable photoluminescence, good biocompatibility, low toxicity, and excellent dispersibility in water, make them a promising candidate for biomedical applications [1]. With the functionalization of GQDs, it is possible to modify their surface structure by adding other functional groups thus altering photoluminescence and enhancing their other properties [2]. Gamma irradiation proved to be a simple and eco-friendly method for subsequent modification of carbon nanomaterials [3, 4]. Here, we present a simple, one-step method for functionalization of GQDs with gamma irradiation in the presence of amino acid L-cysteine as an S, N heteroatom donor and isopropyl alcohol as a radical scavenger. Water dispersion of GQDs with 1 vol% isopropyl alcohol and 2 mass% of L-cysteine was purged with Ar gas for 15 minutes and then exposed to gamma irradiation at doses: 25, 50 and 200 kGy. The optical and structural properties of obtained S, N-GQDs were investigated using Ultraviolet-visible spectroscopy (UV-Vis), Fourier-Transform Infrared spectroscopy (FTIR), Photoluminescence spectroscopy (PL), Atomic force microscopy (AFM) and Dynamic light scattering (DLS). Successful doping of S and N heteroatoms in the structure of irradiated GQDs was confirmed with FTIR analysis through detected S-H, C=S, and N-H stretching vibrations. Also, an improvement in photoluminescence quantum yield (QY) has been proved by PL measurements. The best result was achieved for the sample irradiated with a dose of 25 kGy. PL QY of this sample was 15 times higher compared to non-irradiated p-GQDs, and around 7 times higher up against other irradiated samples. Both AFM and DLS measurements were in correlation and indicated that gamma irradiation increased the layer separation and overall particle diameter of GQDs. The average diameter ranged from 25 nm up to around 30 nm for irradiated samples while the diameter of non-irradiated p-GQDs was 20 nm. The proposed one-step chemical doping provided an improvement in one of the most characteristic features of GQDs- photoluminescence, as well as in morphological properties. Due to this, the obtained S, N-GQDs have great potential for application in medicine as a bioimaging agent",
publisher = "Belgrade : Institute of Physics Belgrade",
journal = "PHOTONICA2021 : 8th International School and Conference on Photonics and HEMMAGINERO workshop : Abstracts of Tutorial, Keynote, Invited Lectures, Progress Reports and Contributed Papers; August 23-27, 2021; Belgrade",
title = "Enhanced photoluminescence of gamma-irradiated S, N graphene quantum dots",
pages = "87",
url = "https://hdl.handle.net/21.15107/rcub_vinar_10907"
}

Milenković, M., Kleut, D.,& Jovanović, S. P.. (2021). Enhanced photoluminescence of gamma-irradiated S, N graphene quantum dots. in PHOTONICA2021 : 8th International School and Conference on Photonics and HEMMAGINERO workshop : Abstracts of Tutorial, Keynote, Invited Lectures, Progress Reports and Contributed Papers; August 23-27, 2021; Belgrade
Belgrade : Institute of Physics Belgrade., 87.
https://hdl.handle.net/21.15107/rcub_vinar_10907

Milenković M, Kleut D, Jovanović SP. Enhanced photoluminescence of gamma-irradiated S, N graphene quantum dots. in PHOTONICA2021 : 8th International School and Conference on Photonics and HEMMAGINERO workshop : Abstracts of Tutorial, Keynote, Invited Lectures, Progress Reports and Contributed Papers; August 23-27, 2021; Belgrade. 2021;:87.
https://hdl.handle.net/21.15107/rcub_vinar_10907 .

Milenković, Mila, Kleut, Duška, Jovanović, Svetlana P., "Enhanced photoluminescence of gamma-irradiated S, N graphene quantum dots" in PHOTONICA2021 : 8th International School and Conference on Photonics and HEMMAGINERO workshop : Abstracts of Tutorial, Keynote, Invited Lectures, Progress Reports and Contributed Papers; August 23-27, 2021; Belgrade (2021):87,
https://hdl.handle.net/21.15107/rcub_vinar_10907 .

TY  - CONF
AU  - Dorontić, Slađana
AU  - Marković, Olivera
AU  - Kleut, Duška
AU  - Jovanović, Svetlana
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/11419
AB  - Graphene quantum dots (GQDs) were fabricated by simple electrochemical oxidation of graphite electrodes. Modified GQDs were obtained by gamma irradiation of GQDs, EDA, and IPA mixture at a dose of 25 kGy. In this approach, GQDs with the amino groups were produced (25γ-GQDs). These GQDs have shown a high uniformity, good dispersibility in water, and strong photoluminescence in the blue part of the electromagnetic spectrum. Modified GQDs were studied in the optical detection of Co2+ ions. The PL intensities of GQDs were measured in the presence of Co2+ ions in the concentration range 0-7.5 μmol L-1. It was demonstrated that PL intensities decreased linearly in the concentration range 0-2.5 μmol L-1. The value of the coefficient of determination (R2= 0.95949) indicates the potential of 25γ-GQDs for application in optical sensing of Co2+ ions.
PB  - Szeged : University of Szeged
C3  - 27th International Symposium on Analytical and Environmental Problems : Proceedings; November 22-23, 2021; Szeged, Hungary
T1  - Amino Functionalized Graphene Quantum Dots - New Fluorescent Sensor for Co2+ Ions
SP  - 107
EP  - 111
UR  - https://hdl.handle.net/21.15107/rcub_vinar_11419
ER  - 

@conference{
author = "Dorontić, Slađana and Marković, Olivera and Kleut, Duška and Jovanović, Svetlana",
year = "2021",
abstract = "Graphene quantum dots (GQDs) were fabricated by simple electrochemical oxidation of graphite electrodes. Modified GQDs were obtained by gamma irradiation of GQDs, EDA, and IPA mixture at a dose of 25 kGy. In this approach, GQDs with the amino groups were produced (25γ-GQDs). These GQDs have shown a high uniformity, good dispersibility in water, and strong photoluminescence in the blue part of the electromagnetic spectrum. Modified GQDs were studied in the optical detection of Co2+ ions. The PL intensities of GQDs were measured in the presence of Co2+ ions in the concentration range 0-7.5 μmol L-1. It was demonstrated that PL intensities decreased linearly in the concentration range 0-2.5 μmol L-1. The value of the coefficient of determination (R2= 0.95949) indicates the potential of 25γ-GQDs for application in optical sensing of Co2+ ions.",
publisher = "Szeged : University of Szeged",
journal = "27th International Symposium on Analytical and Environmental Problems : Proceedings; November 22-23, 2021; Szeged, Hungary",
title = "Amino Functionalized Graphene Quantum Dots - New Fluorescent Sensor for Co2+ Ions",
pages = "107-111",
url = "https://hdl.handle.net/21.15107/rcub_vinar_11419"
}

Dorontić, S., Marković, O., Kleut, D.,& Jovanović, S.. (2021). Amino Functionalized Graphene Quantum Dots - New Fluorescent Sensor for Co2+ Ions. in 27th International Symposium on Analytical and Environmental Problems : Proceedings; November 22-23, 2021; Szeged, Hungary
Szeged : University of Szeged., 107-111.
https://hdl.handle.net/21.15107/rcub_vinar_11419

Dorontić S, Marković O, Kleut D, Jovanović S. Amino Functionalized Graphene Quantum Dots - New Fluorescent Sensor for Co2+ Ions. in 27th International Symposium on Analytical and Environmental Problems : Proceedings; November 22-23, 2021; Szeged, Hungary. 2021;:107-111.
https://hdl.handle.net/21.15107/rcub_vinar_11419 .

Dorontić, Slađana, Marković, Olivera, Kleut, Duška, Jovanović, Svetlana, "Amino Functionalized Graphene Quantum Dots - New Fluorescent Sensor for Co2+ Ions" in 27th International Symposium on Analytical and Environmental Problems : Proceedings; November 22-23, 2021; Szeged, Hungary (2021):107-111,
https://hdl.handle.net/21.15107/rcub_vinar_11419 .

TY  - CONF
AU  - Dorontić, Slađana
AU  - Marković, Olivera S.
AU  - Kleut, Duška
AU  - Jovanović, Svetlana P.
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12499
AB  - We produced Graphene Quantum Dots (GQDs) by electrochemical oxidation of graphite rods and exposed them to gamma irradiation at a dose of 200 kGy, in the presence of ethylene-diamine. Before irradiation, oxygen was removed from the GQDs dispersion by purging with Ar. These conditions induced both chemical reduction as well as the incorporation of N atoms in the structure of GQDs. Thus, N-doped GQDs were produced. The morphology of dots was investigated using atomic force microscopy. UV-Vis and photoluminescence spectroscopy were used to investigate the optical properties of modified GQDs. The changes in the intensities of PL emission spectra were studied in the presence of different concentrations of Pd2+ and pesticide carbofuran. We observed promising results for the application of N-doped GQDs for non-enzymatic PL detection of selected metal ions and molecules of pesticide.
PB  - Szeged : University of Szeged
C3  - 27th International Symposium on Analytical and Environmental Problems, Szeged, Hungary November 22-23, 2021
T1  - N-doped graphene quantum dots for detection of palladium(II) ions and carbofuran
SP  - 143
EP  - 147
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12499
ER  - 

@conference{
author = "Dorontić, Slađana and Marković, Olivera S. and Kleut, Duška and Jovanović, Svetlana P.",
year = "2021",
abstract = "We produced Graphene Quantum Dots (GQDs) by electrochemical oxidation of graphite rods and exposed them to gamma irradiation at a dose of 200 kGy, in the presence of ethylene-diamine. Before irradiation, oxygen was removed from the GQDs dispersion by purging with Ar. These conditions induced both chemical reduction as well as the incorporation of N atoms in the structure of GQDs. Thus, N-doped GQDs were produced. The morphology of dots was investigated using atomic force microscopy. UV-Vis and photoluminescence spectroscopy were used to investigate the optical properties of modified GQDs. The changes in the intensities of PL emission spectra were studied in the presence of different concentrations of Pd2+ and pesticide carbofuran. We observed promising results for the application of N-doped GQDs for non-enzymatic PL detection of selected metal ions and molecules of pesticide.",
publisher = "Szeged : University of Szeged",
journal = "27th International Symposium on Analytical and Environmental Problems, Szeged, Hungary November 22-23, 2021",
title = "N-doped graphene quantum dots for detection of palladium(II) ions and carbofuran",
pages = "143-147",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12499"
}

Dorontić, S., Marković, O. S., Kleut, D.,& Jovanović, S. P.. (2021). N-doped graphene quantum dots for detection of palladium(II) ions and carbofuran. in 27th International Symposium on Analytical and Environmental Problems, Szeged, Hungary November 22-23, 2021
Szeged : University of Szeged., 143-147.
https://hdl.handle.net/21.15107/rcub_vinar_12499

Dorontić S, Marković OS, Kleut D, Jovanović SP. N-doped graphene quantum dots for detection of palladium(II) ions and carbofuran. in 27th International Symposium on Analytical and Environmental Problems, Szeged, Hungary November 22-23, 2021. 2021;:143-147.
https://hdl.handle.net/21.15107/rcub_vinar_12499 .

Dorontić, Slađana, Marković, Olivera S., Kleut, Duška, Jovanović, Svetlana P., "N-doped graphene quantum dots for detection of palladium(II) ions and carbofuran" in 27th International Symposium on Analytical and Environmental Problems, Szeged, Hungary November 22-23, 2021 (2021):143-147,
https://hdl.handle.net/21.15107/rcub_vinar_12499 .

TY  - CONF
AU  - Dorontić, Slađana
AU  - Marković, Olivera S.
AU  - Kleut, Duška
AU  - Jovanović, Svetlana P.
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/12501
AB  - In the era of pollution and hazardous materials, new methods for the detection of pollutantsin the environment are urgently needed. Due to their specific features such asphotoluminescence (PL) in the visible part of the spectrum, dispersibility in water, andorganic solvents, nontoxicity, and biocompatibility, graphene quantum dots (GQDs) attractattention in optical sensing of various ions and molecules. In this study, pristine graphenequantum dots (p-GQDs) were produced in a simple single-step electrochemical top-downapproach using graphite electrodes as a starting material, and dispersion of sodiumhydroxidein 96% ethanol as a medium for electrochemical reaction. These p-GQDs weregamma-irradiated in a dose of 25 kGy in presence of ethylenediamine in Ar medium tointroduce amino groups in their crystal lattice. Results obtained from AFM microscopyindicate the height-uniformity of irradiated GQDs. The presence of amino groups in GQDswas confirmed by FTIR, XPS, and UV-Vis spectroscopies. According to results obtainedfrom PL spectroscopy, a significant narrowing of emission band in irradiated GQDs wasobserved. In further research, these GQDs were investigated as a potential PL sensor for ironwhich is one of the most abundant heavy metal in the environment. In the preliminaryinvestigation, a water dispersion of irradiated GQDs was mixed with Fe(III) solution inconcentrations of 50 and 100 μM. Using a PL spectroscopy the PL intensity of irradiatedGQDs in presence of Fe (III) was measured. From the obtained results, it can be seen thatFe(III) ions lead to quenching of GQDs PL intensity. Then, PL intensities were measured inpresence of Fe(III) ions in concentration range 0-100 μM. With an increase of Fe(III)concentration, the PL intensity of GQDs decreased. It can be concluded that gammairradiatedamino-doped GQDs have significant potential in the so-called ,,turn of“ detectionof Fe(III) ions in the aqueous medium.
PB  - Belgrade : Institute of Technical Sciences of SASA
C3  - 19th Young Researchers’ Conference - Materials Science and Engineering : Program and the Book of Abstracts
T1  - Graphene quantum dots with amino groups as a potential photoluminescent probe for Fe(III) ions
SP  - 35
EP  - 35
UR  - https://hdl.handle.net/21.15107/rcub_vinar_12501
ER  - 

@conference{
author = "Dorontić, Slađana and Marković, Olivera S. and Kleut, Duška and Jovanović, Svetlana P.",
year = "2021",
abstract = "In the era of pollution and hazardous materials, new methods for the detection of pollutantsin the environment are urgently needed. Due to their specific features such asphotoluminescence (PL) in the visible part of the spectrum, dispersibility in water, andorganic solvents, nontoxicity, and biocompatibility, graphene quantum dots (GQDs) attractattention in optical sensing of various ions and molecules. In this study, pristine graphenequantum dots (p-GQDs) were produced in a simple single-step electrochemical top-downapproach using graphite electrodes as a starting material, and dispersion of sodiumhydroxidein 96% ethanol as a medium for electrochemical reaction. These p-GQDs weregamma-irradiated in a dose of 25 kGy in presence of ethylenediamine in Ar medium tointroduce amino groups in their crystal lattice. Results obtained from AFM microscopyindicate the height-uniformity of irradiated GQDs. The presence of amino groups in GQDswas confirmed by FTIR, XPS, and UV-Vis spectroscopies. According to results obtainedfrom PL spectroscopy, a significant narrowing of emission band in irradiated GQDs wasobserved. In further research, these GQDs were investigated as a potential PL sensor for ironwhich is one of the most abundant heavy metal in the environment. In the preliminaryinvestigation, a water dispersion of irradiated GQDs was mixed with Fe(III) solution inconcentrations of 50 and 100 μM. Using a PL spectroscopy the PL intensity of irradiatedGQDs in presence of Fe (III) was measured. From the obtained results, it can be seen thatFe(III) ions lead to quenching of GQDs PL intensity. Then, PL intensities were measured inpresence of Fe(III) ions in concentration range 0-100 μM. With an increase of Fe(III)concentration, the PL intensity of GQDs decreased. It can be concluded that gammairradiatedamino-doped GQDs have significant potential in the so-called ,,turn of“ detectionof Fe(III) ions in the aqueous medium.",
publisher = "Belgrade : Institute of Technical Sciences of SASA",
journal = "19th Young Researchers’ Conference - Materials Science and Engineering : Program and the Book of Abstracts",
title = "Graphene quantum dots with amino groups as a potential photoluminescent probe for Fe(III) ions",
pages = "35-35",
url = "https://hdl.handle.net/21.15107/rcub_vinar_12501"
}

Dorontić, S., Marković, O. S., Kleut, D.,& Jovanović, S. P.. (2021). Graphene quantum dots with amino groups as a potential photoluminescent probe for Fe(III) ions. in 19th Young Researchers’ Conference - Materials Science and Engineering : Program and the Book of Abstracts
Belgrade : Institute of Technical Sciences of SASA., 35-35.
https://hdl.handle.net/21.15107/rcub_vinar_12501

Dorontić S, Marković OS, Kleut D, Jovanović SP. Graphene quantum dots with amino groups as a potential photoluminescent probe for Fe(III) ions. in 19th Young Researchers’ Conference - Materials Science and Engineering : Program and the Book of Abstracts. 2021;:35-35.
https://hdl.handle.net/21.15107/rcub_vinar_12501 .

Dorontić, Slađana, Marković, Olivera S., Kleut, Duška, Jovanović, Svetlana P., "Graphene quantum dots with amino groups as a potential photoluminescent probe for Fe(III) ions" in 19th Young Researchers’ Conference - Materials Science and Engineering : Program and the Book of Abstracts (2021):35-35,
https://hdl.handle.net/21.15107/rcub_vinar_12501 .

TY  - JOUR
AU  - Budimir, Milica
AU  - Marković, Zoran M.
AU  - Vajdak, Jan
AU  - Jovanović, Svetlana P.
AU  - Kubat, Pavel
AU  - Humpoliček, Petr
AU  - Mičušik, Matej
AU  - Danko, Martin
AU  - Barras, Alexandre
AU  - Milivojević, Dušan
AU  - Špitalsky, Zdenko
AU  - Boukherroub, Rabah
AU  - Todorović-Marković, Biljana
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9746
AB  - Persistent microbial contamination of medical implant surfaces is becoming a serious threat to public health. This is principally due to antibiotic-resistant bacterial strains and the formation of bacterial biofilms. The development of novel antibacterial materials that will effectively fight both Gram-positive and Gram-negative bacteria and prevent biofilm formation represents a big challenge for researchers in the last few decades. In the present work, we report an antibacterial hydrophobic carbon quantum dots/polyurethane nanocomposite (hCQD-PU), with enhanced antibacterial properties induced by pre-treatment with gamma-irradiation. Hydrophobic quantum dots (hCQDs), which are capable of generating reactive oxygen species (ROS) upon irradiation with low-power blue light (470 nm), have been integrated into the polyurethane (PU) polymer matrix to form a photoactive nanocomposite. To modify its physical and chemical properties and improve its antibacterial efficacy, various doses of gamma irradiation (1, 10, and 200 kGy) in the air environment were applied to the formed nanocomposite. Gamma-irradiation pre-treatment significantly influenced the rise in ROS production, therefore, the prooxidative activity under the blue-light illumination of hCQD-PU was also significantly improved. The best antibacterial activity was demonstrated by the hCQD-PU nanocomposite irradiated with a dose of 200 kGy, with the complete eradication of Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) bacteria after 15 min of exposure to the blue lamp. © 2021 Elsevier Ltd
T2  - Radiation Physics and Chemistry
T1  - Enhanced visible light-triggered antibacterial activity of carbon quantum dots/polyurethane nanocomposites by gamma rays induced pre-treatment
VL  - 185
SP  - 109499
DO  - 10.1016/j.radphyschem.2021.109499
ER  - 

@article{
author = "Budimir, Milica and Marković, Zoran M. and Vajdak, Jan and Jovanović, Svetlana P. and Kubat, Pavel and Humpoliček, Petr and Mičušik, Matej and Danko, Martin and Barras, Alexandre and Milivojević, Dušan and Špitalsky, Zdenko and Boukherroub, Rabah and Todorović-Marković, Biljana",
year = "2021",
abstract = "Persistent microbial contamination of medical implant surfaces is becoming a serious threat to public health. This is principally due to antibiotic-resistant bacterial strains and the formation of bacterial biofilms. The development of novel antibacterial materials that will effectively fight both Gram-positive and Gram-negative bacteria and prevent biofilm formation represents a big challenge for researchers in the last few decades. In the present work, we report an antibacterial hydrophobic carbon quantum dots/polyurethane nanocomposite (hCQD-PU), with enhanced antibacterial properties induced by pre-treatment with gamma-irradiation. Hydrophobic quantum dots (hCQDs), which are capable of generating reactive oxygen species (ROS) upon irradiation with low-power blue light (470 nm), have been integrated into the polyurethane (PU) polymer matrix to form a photoactive nanocomposite. To modify its physical and chemical properties and improve its antibacterial efficacy, various doses of gamma irradiation (1, 10, and 200 kGy) in the air environment were applied to the formed nanocomposite. Gamma-irradiation pre-treatment significantly influenced the rise in ROS production, therefore, the prooxidative activity under the blue-light illumination of hCQD-PU was also significantly improved. The best antibacterial activity was demonstrated by the hCQD-PU nanocomposite irradiated with a dose of 200 kGy, with the complete eradication of Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) bacteria after 15 min of exposure to the blue lamp. © 2021 Elsevier Ltd",
journal = "Radiation Physics and Chemistry",
title = "Enhanced visible light-triggered antibacterial activity of carbon quantum dots/polyurethane nanocomposites by gamma rays induced pre-treatment",
volume = "185",
pages = "109499",
doi = "10.1016/j.radphyschem.2021.109499"
}

Budimir, M., Marković, Z. M., Vajdak, J., Jovanović, S. P., Kubat, P., Humpoliček, P., Mičušik, M., Danko, M., Barras, A., Milivojević, D., Špitalsky, Z., Boukherroub, R.,& Todorović-Marković, B.. (2021). Enhanced visible light-triggered antibacterial activity of carbon quantum dots/polyurethane nanocomposites by gamma rays induced pre-treatment. in Radiation Physics and Chemistry, 185, 109499.
https://doi.org/10.1016/j.radphyschem.2021.109499

Budimir M, Marković ZM, Vajdak J, Jovanović SP, Kubat P, Humpoliček P, Mičušik M, Danko M, Barras A, Milivojević D, Špitalsky Z, Boukherroub R, Todorović-Marković B. Enhanced visible light-triggered antibacterial activity of carbon quantum dots/polyurethane nanocomposites by gamma rays induced pre-treatment. in Radiation Physics and Chemistry. 2021;185:109499.
doi:10.1016/j.radphyschem.2021.109499 .

Budimir, Milica, Marković, Zoran M., Vajdak, Jan, Jovanović, Svetlana P., Kubat, Pavel, Humpoliček, Petr, Mičušik, Matej, Danko, Martin, Barras, Alexandre, Milivojević, Dušan, Špitalsky, Zdenko, Boukherroub, Rabah, Todorović-Marković, Biljana, "Enhanced visible light-triggered antibacterial activity of carbon quantum dots/polyurethane nanocomposites by gamma rays induced pre-treatment" in Radiation Physics and Chemistry, 185 (2021):109499,
https://doi.org/10.1016/j.radphyschem.2021.109499 . .

TY  - CONF
AU  - Mišović, Aleksandra
AU  - Bonasera, Aurelio
AU  - Budimir, Milica
AU  - Jovanović, Svetlana
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/11425
AB  - Graphene oxide (GO) was produced using the Hummers' method while silver nanowires (AgNWs) were obtained by polyol synthesis. Composite was produced by simple mixing of GO and AgNWs dispersions. The composite was produced in a form of free/standing films by vacuum filtration and exposed to gamma irradiation in an oxygen-free atmosphere. After irradiation, without any additional cleaning, the structure, morphology and electrical properties were investigated. Gamma irradiation was shown to be an efficient tool to induce a chemical reduction of GO, and it was able to improve the electrical conductivity of produced composites. Due to avoiding the usage of reagents and solvents, this method belongs to green chemical approaches.
PB  - Szeged : University of Szeged
C3  - 27th International Symposium on Analytical and Environmental Problems : Proceedings; November 22-23, 2021; Szeged, Hungary
T1  - Gamma Irradiation as a Tool for Modification of Graphene Oxide-Silver Nanowires Composites
SP  - 223
EP  - 227
UR  - https://hdl.handle.net/21.15107/rcub_vinar_11425
ER  - 

@conference{
author = "Mišović, Aleksandra and Bonasera, Aurelio and Budimir, Milica and Jovanović, Svetlana",
year = "2021",
abstract = "Graphene oxide (GO) was produced using the Hummers' method while silver nanowires (AgNWs) were obtained by polyol synthesis. Composite was produced by simple mixing of GO and AgNWs dispersions. The composite was produced in a form of free/standing films by vacuum filtration and exposed to gamma irradiation in an oxygen-free atmosphere. After irradiation, without any additional cleaning, the structure, morphology and electrical properties were investigated. Gamma irradiation was shown to be an efficient tool to induce a chemical reduction of GO, and it was able to improve the electrical conductivity of produced composites. Due to avoiding the usage of reagents and solvents, this method belongs to green chemical approaches.",
publisher = "Szeged : University of Szeged",
journal = "27th International Symposium on Analytical and Environmental Problems : Proceedings; November 22-23, 2021; Szeged, Hungary",
title = "Gamma Irradiation as a Tool for Modification of Graphene Oxide-Silver Nanowires Composites",
pages = "223-227",
url = "https://hdl.handle.net/21.15107/rcub_vinar_11425"
}

Mišović, A., Bonasera, A., Budimir, M.,& Jovanović, S.. (2021). Gamma Irradiation as a Tool for Modification of Graphene Oxide-Silver Nanowires Composites. in 27th International Symposium on Analytical and Environmental Problems : Proceedings; November 22-23, 2021; Szeged, Hungary
Szeged : University of Szeged., 223-227.
https://hdl.handle.net/21.15107/rcub_vinar_11425

Mišović A, Bonasera A, Budimir M, Jovanović S. Gamma Irradiation as a Tool for Modification of Graphene Oxide-Silver Nanowires Composites. in 27th International Symposium on Analytical and Environmental Problems : Proceedings; November 22-23, 2021; Szeged, Hungary. 2021;:223-227.
https://hdl.handle.net/21.15107/rcub_vinar_11425 .

Mišović, Aleksandra, Bonasera, Aurelio, Budimir, Milica, Jovanović, Svetlana, "Gamma Irradiation as a Tool for Modification of Graphene Oxide-Silver Nanowires Composites" in 27th International Symposium on Analytical and Environmental Problems : Proceedings; November 22-23, 2021; Szeged, Hungary (2021):223-227,
https://hdl.handle.net/21.15107/rcub_vinar_11425 .

TY  - JOUR
AU  - Di Santo, Riccardo
AU  - Romanò, Sabrina
AU  - Mazzini, Alberto
AU  - Jovanović, Svetlana P.
AU  - Nocca, Giuseppina
AU  - Campi, Gaetano
AU  - Papi, Massimiliano
AU  - De Spirito, Marco
AU  - Di Giacinto, Flavio
AU  - Ciasca, Gabriele
PY  - 2021
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/9832
AB  - Exosomes (EXOs) are nano-sized vesicles secreted by most cell types. They are abundant in bio-fluids and harbor specific molecular constituents from their parental cells. Due to these characteristics, EXOs have a great potential in cancer diagnostics for liquid biopsy and personalized medicine. Despite this unique potential, EXOs are not yet widely applied in clinical settings, with two main factors hindering their translational process in diagnostics. Firstly, conventional extraction methods are time-consuming, require large sample volumes and expensive equipment, and often do not provide high-purity samples. Secondly, characterization methods have some limitations, because they are often qualitative, need extensive labeling or complex sampling procedures that can induce artifacts. In this context, novel label-free approaches are rapidly emerging, and are holding potential to revolutionize EXO diagnostics. These methods include the use of nanodevices for EXO purification, and vibrational spectroscopies, scattering, and nanoindentation for characterization. In this progress report, we summarize recent key advances in label-free techniques for EXO purification and characterization. We point out that these methods contribute to reducing costs and processing times, provide complementary information compared to the conventional characterization techniques, and enhance flexibility, thus favoring the discovery of novel and unexplored EXO-based biomarkers. In this process, the impact of nanotechnology is systematically highlighted, showing how the effectiveness of these techniques can be enhanced using nanomaterials, such as plasmonic nanoparticles and nanostructured surfaces, which enable the exploitation of advanced physical phenomena occurring at the nanoscale level.
T2  - Nanomaterials
T1  - Recent advances in the label-free characterization of exosomes for cancer liquid biopsy: From scattering and spectroscopy to nanoindentation and nanodevices
VL  - 11
IS  - 6
SP  - 1476
DO  - 10.3390/nano11061476
ER  - 

@article{
author = "Di Santo, Riccardo and Romanò, Sabrina and Mazzini, Alberto and Jovanović, Svetlana P. and Nocca, Giuseppina and Campi, Gaetano and Papi, Massimiliano and De Spirito, Marco and Di Giacinto, Flavio and Ciasca, Gabriele",
year = "2021",
abstract = "Exosomes (EXOs) are nano-sized vesicles secreted by most cell types. They are abundant in bio-fluids and harbor specific molecular constituents from their parental cells. Due to these characteristics, EXOs have a great potential in cancer diagnostics for liquid biopsy and personalized medicine. Despite this unique potential, EXOs are not yet widely applied in clinical settings, with two main factors hindering their translational process in diagnostics. Firstly, conventional extraction methods are time-consuming, require large sample volumes and expensive equipment, and often do not provide high-purity samples. Secondly, characterization methods have some limitations, because they are often qualitative, need extensive labeling or complex sampling procedures that can induce artifacts. In this context, novel label-free approaches are rapidly emerging, and are holding potential to revolutionize EXO diagnostics. These methods include the use of nanodevices for EXO purification, and vibrational spectroscopies, scattering, and nanoindentation for characterization. In this progress report, we summarize recent key advances in label-free techniques for EXO purification and characterization. We point out that these methods contribute to reducing costs and processing times, provide complementary information compared to the conventional characterization techniques, and enhance flexibility, thus favoring the discovery of novel and unexplored EXO-based biomarkers. In this process, the impact of nanotechnology is systematically highlighted, showing how the effectiveness of these techniques can be enhanced using nanomaterials, such as plasmonic nanoparticles and nanostructured surfaces, which enable the exploitation of advanced physical phenomena occurring at the nanoscale level.",
journal = "Nanomaterials",
title = "Recent advances in the label-free characterization of exosomes for cancer liquid biopsy: From scattering and spectroscopy to nanoindentation and nanodevices",
volume = "11",
number = "6",
pages = "1476",
doi = "10.3390/nano11061476"
}

Di Santo, R., Romanò, S., Mazzini, A., Jovanović, S. P., Nocca, G., Campi, G., Papi, M., De Spirito, M., Di Giacinto, F.,& Ciasca, G.. (2021). Recent advances in the label-free characterization of exosomes for cancer liquid biopsy: From scattering and spectroscopy to nanoindentation and nanodevices. in Nanomaterials, 11(6), 1476.
https://doi.org/10.3390/nano11061476

Di Santo R, Romanò S, Mazzini A, Jovanović SP, Nocca G, Campi G, Papi M, De Spirito M, Di Giacinto F, Ciasca G. Recent advances in the label-free characterization of exosomes for cancer liquid biopsy: From scattering and spectroscopy to nanoindentation and nanodevices. in Nanomaterials. 2021;11(6):1476.
doi:10.3390/nano11061476 .

Di Santo, Riccardo, Romanò, Sabrina, Mazzini, Alberto, Jovanović, Svetlana P., Nocca, Giuseppina, Campi, Gaetano, Papi, Massimiliano, De Spirito, Marco, Di Giacinto, Flavio, Ciasca, Gabriele, "Recent advances in the label-free characterization of exosomes for cancer liquid biopsy: From scattering and spectroscopy to nanoindentation and nanodevices" in Nanomaterials, 11, no. 6 (2021):1476,
https://doi.org/10.3390/nano11061476 . .