TY  - JOUR
AU  - Anđelković, Ljubica
AU  - Šuljagić, Marija
AU  - Pavlović, Vladimir
AU  - Mirković, Miljana
AU  - Vrbica, Boško
AU  - Novaković, Irena
AU  - Stanković, Dalibor
AU  - Kremenović, Aleksandar
AU  - Uskoković, Vuk
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/13175
AB  - Metals and metal oxides have subpar antibacterial activities compared to those of small-molecule antibiotics, yet there are hopes that with proper compositional and structural adjustments this gap might be bridged. In this study, titanium dioxide (TiO2) nanoparticles were mechanically activated and combined with particulate silver through simple reduction process elicited by UV irradiation and assisted with the ultrasound. The resulting powders in various combinations (Ag vs. no Ag, activated vs. non-activated) were characterized using a range of experimental techniques and assessed for their antibacterial activities. The preparation procedure presented in this work prevails over the disadvantages of many chemical routes, most critically by avoiding the use of toxic substances. The mechanical activation did not reduce the particle size or crystallinity of TiO2 nor did it consistently alter the bandgap, yet it enabled the doubling of the amount of silver incorporable into the material. Further, while both mechanical activation and the addition of silver in the amount not exceeding 0.5 wt% produced barely detectable structural changes in the material, they both augmented its antibacterial activity. The precursor TiO2 powder produced no inhibition zone against any of the four bacterial species tested, while the mechanical activation of TiO2 led to the formation of distinct inhibition zones against each of the four bacterial species tested. The addition of silver to activated TiO2 further widened the inhibition zones and it also imparted the antibacterial activity to non-activated TiO2. The boost in the antibacterial activity achieved by the short mechanical activation was of a similar magnitude as the boost obtained after the addition of silver. The antibacterial activity was not different for different species when no silver was added to the system. However, with the addition of silver, species selectivity was obtained, as the composites were more effective against the two Gram-negative species (Escherichia coli and Klebsiella pneumoniae) than against the two Gram-positive ones (Staphylococcus aureus and Bacillus subtilis). The antibacterial activity increased with the addition of silver in the broth assay, but it was mediocre compared to that detected in the agar assay, attesting to the poor dispersability of the powders and their best performance when the bacterial cells migrate to the composite surface than vice versa. The findings of this study give hope that with appropriate microstructural or compositional alterations, the antibacterial activity of metal oxide powders and inorganic materials in general can be made comparable to that of small-molecule antibiotics.
T2  - Colloids and Surfaces A: Physicochemical and Engineering Aspects
T1  - Mechanical activation and silver supplementation as determinants of the antibacterial activity of titanium dioxide nanoparticles
VL  - 691
SP  - 133890
DO  - 10.1016/j.colsurfa.2024.133890
ER  - 

@article{
author = "Anđelković, Ljubica and Šuljagić, Marija and Pavlović, Vladimir and Mirković, Miljana and Vrbica, Boško and Novaković, Irena and Stanković, Dalibor and Kremenović, Aleksandar and Uskoković, Vuk",
year = "2024",
abstract = "Metals and metal oxides have subpar antibacterial activities compared to those of small-molecule antibiotics, yet there are hopes that with proper compositional and structural adjustments this gap might be bridged. In this study, titanium dioxide (TiO2) nanoparticles were mechanically activated and combined with particulate silver through simple reduction process elicited by UV irradiation and assisted with the ultrasound. The resulting powders in various combinations (Ag vs. no Ag, activated vs. non-activated) were characterized using a range of experimental techniques and assessed for their antibacterial activities. The preparation procedure presented in this work prevails over the disadvantages of many chemical routes, most critically by avoiding the use of toxic substances. The mechanical activation did not reduce the particle size or crystallinity of TiO2 nor did it consistently alter the bandgap, yet it enabled the doubling of the amount of silver incorporable into the material. Further, while both mechanical activation and the addition of silver in the amount not exceeding 0.5 wt% produced barely detectable structural changes in the material, they both augmented its antibacterial activity. The precursor TiO2 powder produced no inhibition zone against any of the four bacterial species tested, while the mechanical activation of TiO2 led to the formation of distinct inhibition zones against each of the four bacterial species tested. The addition of silver to activated TiO2 further widened the inhibition zones and it also imparted the antibacterial activity to non-activated TiO2. The boost in the antibacterial activity achieved by the short mechanical activation was of a similar magnitude as the boost obtained after the addition of silver. The antibacterial activity was not different for different species when no silver was added to the system. However, with the addition of silver, species selectivity was obtained, as the composites were more effective against the two Gram-negative species (Escherichia coli and Klebsiella pneumoniae) than against the two Gram-positive ones (Staphylococcus aureus and Bacillus subtilis). The antibacterial activity increased with the addition of silver in the broth assay, but it was mediocre compared to that detected in the agar assay, attesting to the poor dispersability of the powders and their best performance when the bacterial cells migrate to the composite surface than vice versa. The findings of this study give hope that with appropriate microstructural or compositional alterations, the antibacterial activity of metal oxide powders and inorganic materials in general can be made comparable to that of small-molecule antibiotics.",
journal = "Colloids and Surfaces A: Physicochemical and Engineering Aspects",
title = "Mechanical activation and silver supplementation as determinants of the antibacterial activity of titanium dioxide nanoparticles",
volume = "691",
pages = "133890",
doi = "10.1016/j.colsurfa.2024.133890"
}

Anđelković, L., Šuljagić, M., Pavlović, V., Mirković, M., Vrbica, B., Novaković, I., Stanković, D., Kremenović, A.,& Uskoković, V.. (2024). Mechanical activation and silver supplementation as determinants of the antibacterial activity of titanium dioxide nanoparticles. in Colloids and Surfaces A: Physicochemical and Engineering Aspects, 691, 133890.
https://doi.org/10.1016/j.colsurfa.2024.133890

Anđelković L, Šuljagić M, Pavlović V, Mirković M, Vrbica B, Novaković I, Stanković D, Kremenović A, Uskoković V. Mechanical activation and silver supplementation as determinants of the antibacterial activity of titanium dioxide nanoparticles. in Colloids and Surfaces A: Physicochemical and Engineering Aspects. 2024;691:133890.
doi:10.1016/j.colsurfa.2024.133890 .

Anđelković, Ljubica, Šuljagić, Marija, Pavlović, Vladimir, Mirković, Miljana, Vrbica, Boško, Novaković, Irena, Stanković, Dalibor, Kremenović, Aleksandar, Uskoković, Vuk, "Mechanical activation and silver supplementation as determinants of the antibacterial activity of titanium dioxide nanoparticles" in Colloids and Surfaces A: Physicochemical and Engineering Aspects, 691 (2024):133890,
https://doi.org/10.1016/j.colsurfa.2024.133890 . .

TY  - JOUR
AU  - Milikić, Jadranka
AU  - Nastasić, Ana
AU  - Rakočević, Lazar
AU  - Radinović, Kristina
AU  - Stojadinović, Stevan
AU  - Stanković, Dalibor
AU  - Šljukić, Biljana
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/13174
AB  - Three different iron-based electrocatalysts deposited on reduced graphene oxide (Fe/rGO, FeNi/rGO, and FeCu/ rGO) were synthesized and examined for oxygen reduction and evolution reactions (ORR and OER, respectively) in alkaline media. X-ray powder diffraction analysis, Fourier transform infrared spectroscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy were used for a thorough investigation of physico-chemical properties of FeM/rGO electrocatalysts. XPS analysis indicated the presence of transition metals in higher oxidation states. Onset potentials during OER were found to be 1.51, 1.64, and 1.71 V for FeNi/rGO, FeCu/rGO, and Fe/rGO, respectively. Moreover, FeNi/rGO showed the highest OER current density (~40 mA cm benchmark OER electrocatalyst, IrO 2 2 at 2 V), two times higher than the -1 , and the lowest Tafel slope (88 mV dec ), lower than IrO . The somewhat better catalytic activity of Fe/rGO for ORR in alkaline media compared to FeNi/rGO and FeCu/rGO was noticed. Tafel slopes of 105, 112, and 113 mV dec 2-1 during ORR were found for Fe/rGO, FeCu/rGO, and FeNi/rGO, respectively. Almost constant ORR current densities during chronoamperometric measurements were noticed for Fe/rGO and FeCu/rGO indicating stable performance.
T2  - Fuel
T1  - FeM/rGO (M = Ni and Cu) as bifunctional oxygen electrode
VL  - 368
SP  - 131654
DO  - 10.1016/j.fuel.2024.131654
ER  - 

@article{
author = "Milikić, Jadranka and Nastasić, Ana and Rakočević, Lazar and Radinović, Kristina and Stojadinović, Stevan and Stanković, Dalibor and Šljukić, Biljana",
year = "2024",
abstract = "Three different iron-based electrocatalysts deposited on reduced graphene oxide (Fe/rGO, FeNi/rGO, and FeCu/ rGO) were synthesized and examined for oxygen reduction and evolution reactions (ORR and OER, respectively) in alkaline media. X-ray powder diffraction analysis, Fourier transform infrared spectroscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy were used for a thorough investigation of physico-chemical properties of FeM/rGO electrocatalysts. XPS analysis indicated the presence of transition metals in higher oxidation states. Onset potentials during OER were found to be 1.51, 1.64, and 1.71 V for FeNi/rGO, FeCu/rGO, and Fe/rGO, respectively. Moreover, FeNi/rGO showed the highest OER current density (~40 mA cm benchmark OER electrocatalyst, IrO 2 2 at 2 V), two times higher than the -1 , and the lowest Tafel slope (88 mV dec ), lower than IrO . The somewhat better catalytic activity of Fe/rGO for ORR in alkaline media compared to FeNi/rGO and FeCu/rGO was noticed. Tafel slopes of 105, 112, and 113 mV dec 2-1 during ORR were found for Fe/rGO, FeCu/rGO, and FeNi/rGO, respectively. Almost constant ORR current densities during chronoamperometric measurements were noticed for Fe/rGO and FeCu/rGO indicating stable performance.",
journal = "Fuel",
title = "FeM/rGO (M = Ni and Cu) as bifunctional oxygen electrode",
volume = "368",
pages = "131654",
doi = "10.1016/j.fuel.2024.131654"
}

Milikić, J., Nastasić, A., Rakočević, L., Radinović, K., Stojadinović, S., Stanković, D.,& Šljukić, B.. (2024). FeM/rGO (M = Ni and Cu) as bifunctional oxygen electrode. in Fuel, 368, 131654.
https://doi.org/10.1016/j.fuel.2024.131654

Milikić J, Nastasić A, Rakočević L, Radinović K, Stojadinović S, Stanković D, Šljukić B. FeM/rGO (M = Ni and Cu) as bifunctional oxygen electrode. in Fuel. 2024;368:131654.
doi:10.1016/j.fuel.2024.131654 .

Milikić, Jadranka, Nastasić, Ana, Rakočević, Lazar, Radinović, Kristina, Stojadinović, Stevan, Stanković, Dalibor, Šljukić, Biljana, "FeM/rGO (M = Ni and Cu) as bifunctional oxygen electrode" in Fuel, 368 (2024):131654,
https://doi.org/10.1016/j.fuel.2024.131654 . .

TY  - JOUR
AU  - Mutić, Tijana
AU  - Ognjanović, Miloš
AU  - Ivković, Đurđa
AU  - Nikolić, Vladimir
AU  - Stanković, Vesna
AU  - Ristivojević, Petar
AU  - Stanković, Dalibor
PY  - 2024
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/13031
AB  - In this study, we successfully prepared a modified nickel oxide (NiO) carbon paste electrode to detect gallic acid (GA). NiO nanoparticles were synthesized by the simple, organic solvent-free chemical coprecipitation method, and the electrochemical properties of the electrode and GA were thoroughly investigated using CV, SWV, and EIS, while morphological properties were examined using ICP-OES, TEM, SEM, and XRD. Excellent catalytic characteristics are displayed by the developed material which facilitates the interaction of the target with the electrode surface. The obtained electrochemical information showed that the incorporation of NiO nanoparticles to the carbon paste electrode effectively facilitates electron transfer processes and enriches the catalytic response of the carbon paste electrode. The fabricated NiO/CPE sensor showed a satisfactory linear relationship between peak current and GA concentration in the broad range of 0.2–100 μM and 100–200 μM with a low detection limit of 0.04 μM and limit of quantification of 0.12 μM at pH 3 of BRBS as supporting electrolyte. The selectivity of the proposed method was satisfactory, with acceptable stability, considerable repeatability, and accurate reproducibility. Moreover, the good practicability performance could be effectuated at the NiO/CPE sensor for the quantitative analysis of GA in bourtree, walnut, primrose, and chamomile tea samples. The results were compared with the standard DPPH test and statistical processing of the results was performed, which confirmed the excellent agreement between the two methods. The developed method can provide a cost-effective, rapid, selective, and sensitive means for GA monitoring. When compared to other works, the developed technique has a wider linear range and lower LOD and LOQ, which makes this work a very important reference for the highly sensitive analysis of GA in the field of food safety.
T2  - Journal of Electroanalytical Chemistry
T1  - Improving gallic acid detection in plant samples: Fabrication and optimization of a sensitive and selective NiO-supported carbon paste electrode
VL  - 960
SP  - 118213
DO  - 10.1016/j.jelechem.2024.118213
ER  - 

@article{
author = "Mutić, Tijana and Ognjanović, Miloš and Ivković, Đurđa and Nikolić, Vladimir and Stanković, Vesna and Ristivojević, Petar and Stanković, Dalibor",
year = "2024",
abstract = "In this study, we successfully prepared a modified nickel oxide (NiO) carbon paste electrode to detect gallic acid (GA). NiO nanoparticles were synthesized by the simple, organic solvent-free chemical coprecipitation method, and the electrochemical properties of the electrode and GA were thoroughly investigated using CV, SWV, and EIS, while morphological properties were examined using ICP-OES, TEM, SEM, and XRD. Excellent catalytic characteristics are displayed by the developed material which facilitates the interaction of the target with the electrode surface. The obtained electrochemical information showed that the incorporation of NiO nanoparticles to the carbon paste electrode effectively facilitates electron transfer processes and enriches the catalytic response of the carbon paste electrode. The fabricated NiO/CPE sensor showed a satisfactory linear relationship between peak current and GA concentration in the broad range of 0.2–100 μM and 100–200 μM with a low detection limit of 0.04 μM and limit of quantification of 0.12 μM at pH 3 of BRBS as supporting electrolyte. The selectivity of the proposed method was satisfactory, with acceptable stability, considerable repeatability, and accurate reproducibility. Moreover, the good practicability performance could be effectuated at the NiO/CPE sensor for the quantitative analysis of GA in bourtree, walnut, primrose, and chamomile tea samples. The results were compared with the standard DPPH test and statistical processing of the results was performed, which confirmed the excellent agreement between the two methods. The developed method can provide a cost-effective, rapid, selective, and sensitive means for GA monitoring. When compared to other works, the developed technique has a wider linear range and lower LOD and LOQ, which makes this work a very important reference for the highly sensitive analysis of GA in the field of food safety.",
journal = "Journal of Electroanalytical Chemistry",
title = "Improving gallic acid detection in plant samples: Fabrication and optimization of a sensitive and selective NiO-supported carbon paste electrode",
volume = "960",
pages = "118213",
doi = "10.1016/j.jelechem.2024.118213"
}

Mutić, T., Ognjanović, M., Ivković, Đ., Nikolić, V., Stanković, V., Ristivojević, P.,& Stanković, D.. (2024). Improving gallic acid detection in plant samples: Fabrication and optimization of a sensitive and selective NiO-supported carbon paste electrode. in Journal of Electroanalytical Chemistry, 960, 118213.
https://doi.org/10.1016/j.jelechem.2024.118213

Mutić T, Ognjanović M, Ivković Đ, Nikolić V, Stanković V, Ristivojević P, Stanković D. Improving gallic acid detection in plant samples: Fabrication and optimization of a sensitive and selective NiO-supported carbon paste electrode. in Journal of Electroanalytical Chemistry. 2024;960:118213.
doi:10.1016/j.jelechem.2024.118213 .

Mutić, Tijana, Ognjanović, Miloš, Ivković, Đurđa, Nikolić, Vladimir, Stanković, Vesna, Ristivojević, Petar, Stanković, Dalibor, "Improving gallic acid detection in plant samples: Fabrication and optimization of a sensitive and selective NiO-supported carbon paste electrode" in Journal of Electroanalytical Chemistry, 960 (2024):118213,
https://doi.org/10.1016/j.jelechem.2024.118213 . .