TY  - CONF
AU  - Pantić, Jelena
AU  - Aleksić, Mara
AU  - Kapetanović, Vera
AU  - Ružić, Dušan
PY  - 2016
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/4923
AB  - Electrochemical behavior of sulfaquinoxaline (SQN) was investigated using cyclic (CV) and differential pulse voltammetry (DPV) at glassy carbon electrode (GCE). CV was applied to investigate the effect of the supporting electrolyte pH on the SQN electrochemical behavior. In the pH range 2.0 – 10.0, the best current response was obtained at pH 7.0 in phosphate buffer. Results indicated that SQN is oxidized in irreversible process. DPV method was optimized, and the linear dependence of peak current vs. SQN concentration was obtained in the range 3×10-6 ‒ 5×10-5 molL-1, with limits of detection and quantification of 1.53×10-6 molL-1 and 5.10×10-6 molL-1, respectively. DPV was successively applied for SQN determination in veterinary medicine NEOCOCCYN WSP, which contains amprolium hydrochloride, as active component too.
PB  - Society of Physical Chemists of Serbia
C3  - PHYSICAL CHEMISTRY 2016 (Proceedings) 13th International Conference on Fundamental and Applied Aspects of Physical Chemistry, September 26-30, 2016, Belgrade, Serbia
T1  - Electrochemical behavior and determination od sulfaquinoxaline at glassy carbon electrode
VL  - II
SP  - 829
EP  - 832
UR  - https://hdl.handle.net/21.15107/rcub_farfar_4923
ER  - 

@conference{
author = "Pantić, Jelena and Aleksić, Mara and Kapetanović, Vera and Ružić, Dušan",
year = "2016",
abstract = "Electrochemical behavior of sulfaquinoxaline (SQN) was investigated using cyclic (CV) and differential pulse voltammetry (DPV) at glassy carbon electrode (GCE). CV was applied to investigate the effect of the supporting electrolyte pH on the SQN electrochemical behavior. In the pH range 2.0 – 10.0, the best current response was obtained at pH 7.0 in phosphate buffer. Results indicated that SQN is oxidized in irreversible process. DPV method was optimized, and the linear dependence of peak current vs. SQN concentration was obtained in the range 3×10-6 ‒ 5×10-5 molL-1, with limits of detection and quantification of 1.53×10-6 molL-1 and 5.10×10-6 molL-1, respectively. DPV was successively applied for SQN determination in veterinary medicine NEOCOCCYN WSP, which contains amprolium hydrochloride, as active component too.",
publisher = "Society of Physical Chemists of Serbia",
journal = "PHYSICAL CHEMISTRY 2016 (Proceedings) 13th International Conference on Fundamental and Applied Aspects of Physical Chemistry, September 26-30, 2016, Belgrade, Serbia",
title = "Electrochemical behavior and determination od sulfaquinoxaline at glassy carbon electrode",
volume = "II",
pages = "829-832",
url = "https://hdl.handle.net/21.15107/rcub_farfar_4923"
}

Pantić, J., Aleksić, M., Kapetanović, V.,& Ružić, D.. (2016). Electrochemical behavior and determination od sulfaquinoxaline at glassy carbon electrode. in PHYSICAL CHEMISTRY 2016 (Proceedings) 13th International Conference on Fundamental and Applied Aspects of Physical Chemistry, September 26-30, 2016, Belgrade, Serbia
Society of Physical Chemists of Serbia., II, 829-832.
https://hdl.handle.net/21.15107/rcub_farfar_4923

Pantić J, Aleksić M, Kapetanović V, Ružić D. Electrochemical behavior and determination od sulfaquinoxaline at glassy carbon electrode. in PHYSICAL CHEMISTRY 2016 (Proceedings) 13th International Conference on Fundamental and Applied Aspects of Physical Chemistry, September 26-30, 2016, Belgrade, Serbia. 2016;II:829-832.
https://hdl.handle.net/21.15107/rcub_farfar_4923 .

Pantić, Jelena, Aleksić, Mara, Kapetanović, Vera, Ružić, Dušan, "Electrochemical behavior and determination od sulfaquinoxaline at glassy carbon electrode" in PHYSICAL CHEMISTRY 2016 (Proceedings) 13th International Conference on Fundamental and Applied Aspects of Physical Chemistry, September 26-30, 2016, Belgrade, Serbia, II (2016):829-832,
https://hdl.handle.net/21.15107/rcub_farfar_4923 .

TY  - JOUR
AU  - Aleksić, Mara
AU  - Pantić, Jelena
AU  - Kapetanović, Vera
PY  - 2014
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/2295
AB  - The electrochemical behavior of a biologically important heterocyclic compound quinoxaline (QUI) was investigated by cyclic voltammetry (CV) in solutions of differing pH, using a glassy carbon electrode (GCE). The reduction of QUI occurs as a quasi-reversible reaction in acid medium, reaching reversibility in alkaline solutions. The kinetic parameters of the electrode process such as αnα, diffusion coefficient (D) and heterogeneous rate constant (ks), were evaluated and discussed. Redox mechanism of QUI was proposed on the basis of experimental results. Reduction process involves a transfer of two electrons and two protons at the pyrazine ring of QUI forming a dihydro-derivative. In acid solutions, the product of QUI reduction undergoes irreversible oxidation in a one-electron process. The electrode processes was found to be diffusion controlled.
AB  - Elektrohemijsko ponašanje biološki značajnog heterocikličnog jedinjenja hinoksalina (QUI) ispitivano je cikličnom voltametrijom (CV) u rastvorima različitih pH vrednosti, korišćenjem electrode odstaklastog ugljenika. Redukcija QUI u kiseloj sredini se odigrava kao kvazi-reverzibilna reakcija, koja u baznoj sredini postaje reverzibilna. Određeni su i razmatrani kinetički parametric elektrodnog procesa kao što su koeficijent αnα, difuzioni koeficijent (D) i konstanta brzine (ks). Na osnovu eksperimentalnih rezultata predložen je mehanizam elektrodne reakcije. U procesu redukcije adiraju se dva elektrona i dva protona na pirazinski prsten hinoksalina i nastaje njegov dihidro derivat. Proizvod redukcije hinoksalina u kiseloj sredini se dalje oksiduje. Ovaj process oksidacije je difuziono kontrolisan, ireverzibilan i odigrava se uz učešće jednog elektrona i jednog protona.
PB  - Univerzitet u Nišu, Niš
T2  - Facta universitatis - series: Physics, Chemistry and Technology
T1  - Evaluation of kinetic parameters and redox mechanism of quinoxaline at glassy carbon electrode
T1  - Određivanje kinetičkih parametara i ispitivanje redoks mehanizma hinoksalina na elektrodi od staklastog ugljenika
VL  - 12
IS  - 1
SP  - 55
EP  - 63
DO  - 10.2298/FUPCT1401055A
ER  - 

@article{
author = "Aleksić, Mara and Pantić, Jelena and Kapetanović, Vera",
year = "2014",
abstract = "The electrochemical behavior of a biologically important heterocyclic compound quinoxaline (QUI) was investigated by cyclic voltammetry (CV) in solutions of differing pH, using a glassy carbon electrode (GCE). The reduction of QUI occurs as a quasi-reversible reaction in acid medium, reaching reversibility in alkaline solutions. The kinetic parameters of the electrode process such as αnα, diffusion coefficient (D) and heterogeneous rate constant (ks), were evaluated and discussed. Redox mechanism of QUI was proposed on the basis of experimental results. Reduction process involves a transfer of two electrons and two protons at the pyrazine ring of QUI forming a dihydro-derivative. In acid solutions, the product of QUI reduction undergoes irreversible oxidation in a one-electron process. The electrode processes was found to be diffusion controlled., Elektrohemijsko ponašanje biološki značajnog heterocikličnog jedinjenja hinoksalina (QUI) ispitivano je cikličnom voltametrijom (CV) u rastvorima različitih pH vrednosti, korišćenjem electrode odstaklastog ugljenika. Redukcija QUI u kiseloj sredini se odigrava kao kvazi-reverzibilna reakcija, koja u baznoj sredini postaje reverzibilna. Određeni su i razmatrani kinetički parametric elektrodnog procesa kao što su koeficijent αnα, difuzioni koeficijent (D) i konstanta brzine (ks). Na osnovu eksperimentalnih rezultata predložen je mehanizam elektrodne reakcije. U procesu redukcije adiraju se dva elektrona i dva protona na pirazinski prsten hinoksalina i nastaje njegov dihidro derivat. Proizvod redukcije hinoksalina u kiseloj sredini se dalje oksiduje. Ovaj process oksidacije je difuziono kontrolisan, ireverzibilan i odigrava se uz učešće jednog elektrona i jednog protona.",
publisher = "Univerzitet u Nišu, Niš",
journal = "Facta universitatis - series: Physics, Chemistry and Technology",
title = "Evaluation of kinetic parameters and redox mechanism of quinoxaline at glassy carbon electrode, Određivanje kinetičkih parametara i ispitivanje redoks mehanizma hinoksalina na elektrodi od staklastog ugljenika",
volume = "12",
number = "1",
pages = "55-63",
doi = "10.2298/FUPCT1401055A"
}

Aleksić, M., Pantić, J.,& Kapetanović, V.. (2014). Evaluation of kinetic parameters and redox mechanism of quinoxaline at glassy carbon electrode. in Facta universitatis - series: Physics, Chemistry and Technology
Univerzitet u Nišu, Niš., 12(1), 55-63.
https://doi.org/10.2298/FUPCT1401055A

Aleksić M, Pantić J, Kapetanović V. Evaluation of kinetic parameters and redox mechanism of quinoxaline at glassy carbon electrode. in Facta universitatis - series: Physics, Chemistry and Technology. 2014;12(1):55-63.
doi:10.2298/FUPCT1401055A .

Aleksić, Mara, Pantić, Jelena, Kapetanović, Vera, "Evaluation of kinetic parameters and redox mechanism of quinoxaline at glassy carbon electrode" in Facta universitatis - series: Physics, Chemistry and Technology, 12, no. 1 (2014):55-63,
https://doi.org/10.2298/FUPCT1401055A . .

TY  - JOUR
AU  - Aleksić, Mara
AU  - Lijeskić, Nikola
AU  - Pantić, Jelena
AU  - Kapetanović, Vera
PY  - 2013
UR  - https://farfar.pharmacy.bg.ac.rs/handle/123456789/2009
AB  - The voltammetric behavior of three cephalosporins: ceftazidime, cefuroxime-axetil and ceftriaxone has been examined in pH range 2.0-8.0 by cyclic voltammetry (CV) and differential pulse voltammetry (DPV), using a hanging mercury drop electrode (HMDE). The effect of pH of the electrolyte solution and scan rate on the peak currents and peak potentials was examined. The nature of the electrode reduction process in acid solution was found to be diffusion controlled for ceftazidime and cefuroxime-axetil, but strongly influenced by adsorption in the case of ceftriaxone reduction. The adsorption and reorientation of the ceftriaxone molecule at the electrode surface caused instability of the voltammetric signal and disabled its determination in the acid medium. Ceftriaxone adsorption decreased with the increase of pH, and at pH>7 the reduction process became diffusion controlled. Based on this study, DPV method was developed, validated and suggested for determination of ceftazidime at pH 2.0, cefuroxime-axetil at pH 3.5 and for ceftriaxone at pH 8.0. Linear concentration ranges, limits of detection (LOD) and quantification (LOQ) were determined. The method was applied for determination of cephalosporins in pharmaceutical dosage forms: Ceftazidime powder, Ceroxim tablets and Longaceph powder for injection solution.
AB  - Voltametrijsko ponašanje tri cephalosporina: ceftazidima, cefuroksim-aksetila i ceftriaksona ispitivano je cikličnom (CV) i diferencijalno pulsnom (DPV) voltametrijom u pH oblasti od 2,0 do 8,0 na visećoj živnoj kapi. Razmatrani su uticaji pH osnovnog elektrolita i brzine promene potencijala na vrednost stuje i potencijala voltametrijskih pikova. Rezultati dobijeni u kiseloj sredini su pokazali da je redukcija ceftazidima i cefuroksim-aksetila difuziono kontrolisan proces, a da je u slučaju ceftriaksona priroda redukcije na elektrodi jako zavisna od adsorpcije. Posledica adsorpcije i reorijentacije molekula ceftriaksona na površini elektrode je nestabilnost i nereproduktivnost voltametrijskog signala što onemogućava određivanje cefriaksona u kiseloj sredini. Intenzitet adsorpcije ceftriaksona opada sa porastom pH i pri pH>7 njegova redukcija postaje difuzijom kontrolisan proces. Na osnovu ovih rezultata predložena je i validirana DPV metoda za određvanje ceftazidima na pH 2,0, cefuroksim-aksetila na pH 3,5 i ceftriaksona na pH 8,0. Određene su vrednosti opsega linearnosti, granice detekcije i određivanja. Metoda je uspešno primenjena za određivanje ovih cefalosporina u farmaceutskim doziranim oblicima i to u Ceroxim tabletama i Ceftazidim i Longaceph prašku za injekcione rastvore.
PB  - Univerzitet u Nišu, Niš
T2  - Facta universitatis - series: Physics, Chemistry and Technology
T1  - Electrochemical behavior and differential pulse voltammetric determination of ceftazidime, cefuroxime-axetil and ceftriaxone
T1  - Elektrohemijsko ponašanje i primena diferencijalno pulsne voltametrije za određivanje ceftazidima, cefuroksim-aksetila i ceftriaksona
VL  - 11
IS  - 1
SP  - 55
EP  - 66
DO  - 10.2298/FUPCT1301055A
ER  - 

@article{
author = "Aleksić, Mara and Lijeskić, Nikola and Pantić, Jelena and Kapetanović, Vera",
year = "2013",
abstract = "The voltammetric behavior of three cephalosporins: ceftazidime, cefuroxime-axetil and ceftriaxone has been examined in pH range 2.0-8.0 by cyclic voltammetry (CV) and differential pulse voltammetry (DPV), using a hanging mercury drop electrode (HMDE). The effect of pH of the electrolyte solution and scan rate on the peak currents and peak potentials was examined. The nature of the electrode reduction process in acid solution was found to be diffusion controlled for ceftazidime and cefuroxime-axetil, but strongly influenced by adsorption in the case of ceftriaxone reduction. The adsorption and reorientation of the ceftriaxone molecule at the electrode surface caused instability of the voltammetric signal and disabled its determination in the acid medium. Ceftriaxone adsorption decreased with the increase of pH, and at pH>7 the reduction process became diffusion controlled. Based on this study, DPV method was developed, validated and suggested for determination of ceftazidime at pH 2.0, cefuroxime-axetil at pH 3.5 and for ceftriaxone at pH 8.0. Linear concentration ranges, limits of detection (LOD) and quantification (LOQ) were determined. The method was applied for determination of cephalosporins in pharmaceutical dosage forms: Ceftazidime powder, Ceroxim tablets and Longaceph powder for injection solution., Voltametrijsko ponašanje tri cephalosporina: ceftazidima, cefuroksim-aksetila i ceftriaksona ispitivano je cikličnom (CV) i diferencijalno pulsnom (DPV) voltametrijom u pH oblasti od 2,0 do 8,0 na visećoj živnoj kapi. Razmatrani su uticaji pH osnovnog elektrolita i brzine promene potencijala na vrednost stuje i potencijala voltametrijskih pikova. Rezultati dobijeni u kiseloj sredini su pokazali da je redukcija ceftazidima i cefuroksim-aksetila difuziono kontrolisan proces, a da je u slučaju ceftriaksona priroda redukcije na elektrodi jako zavisna od adsorpcije. Posledica adsorpcije i reorijentacije molekula ceftriaksona na površini elektrode je nestabilnost i nereproduktivnost voltametrijskog signala što onemogućava određivanje cefriaksona u kiseloj sredini. Intenzitet adsorpcije ceftriaksona opada sa porastom pH i pri pH>7 njegova redukcija postaje difuzijom kontrolisan proces. Na osnovu ovih rezultata predložena je i validirana DPV metoda za određvanje ceftazidima na pH 2,0, cefuroksim-aksetila na pH 3,5 i ceftriaksona na pH 8,0. Određene su vrednosti opsega linearnosti, granice detekcije i određivanja. Metoda je uspešno primenjena za određivanje ovih cefalosporina u farmaceutskim doziranim oblicima i to u Ceroxim tabletama i Ceftazidim i Longaceph prašku za injekcione rastvore.",
publisher = "Univerzitet u Nišu, Niš",
journal = "Facta universitatis - series: Physics, Chemistry and Technology",
title = "Electrochemical behavior and differential pulse voltammetric determination of ceftazidime, cefuroxime-axetil and ceftriaxone, Elektrohemijsko ponašanje i primena diferencijalno pulsne voltametrije za određivanje ceftazidima, cefuroksim-aksetila i ceftriaksona",
volume = "11",
number = "1",
pages = "55-66",
doi = "10.2298/FUPCT1301055A"
}

Aleksić, M., Lijeskić, N., Pantić, J.,& Kapetanović, V.. (2013). Electrochemical behavior and differential pulse voltammetric determination of ceftazidime, cefuroxime-axetil and ceftriaxone. in Facta universitatis - series: Physics, Chemistry and Technology
Univerzitet u Nišu, Niš., 11(1), 55-66.
https://doi.org/10.2298/FUPCT1301055A

Aleksić M, Lijeskić N, Pantić J, Kapetanović V. Electrochemical behavior and differential pulse voltammetric determination of ceftazidime, cefuroxime-axetil and ceftriaxone. in Facta universitatis - series: Physics, Chemistry and Technology. 2013;11(1):55-66.
doi:10.2298/FUPCT1301055A .

Aleksić, Mara, Lijeskić, Nikola, Pantić, Jelena, Kapetanović, Vera, "Electrochemical behavior and differential pulse voltammetric determination of ceftazidime, cefuroxime-axetil and ceftriaxone" in Facta universitatis - series: Physics, Chemistry and Technology, 11, no. 1 (2013):55-66,
https://doi.org/10.2298/FUPCT1301055A . .