The ionization constants (pKa) of ceftazidime, third generation cephalosporin, were determined by potentiometry. Ceftazidime is an ampholyte with four ionizable centers, three acidic centers (two carboxyl groups and amide group) and one basic center (aminothiazole). Potentiometric determinations were performed at 25 °C and constant ionic strength of 0.1 M (NaCl). Experimental data were analyzed by computer software Hyperquad and four pKa values were derived: pKa1 2.55; pKa2 3.94; pKa3 4.54 and pKa4 7.55. According to the obtained pKa values distribution diagram as a function of pH was constructed and distribution of the ceftazidime equilibrium forms was calculated at a pH values of biopharmaceutical significance (pH 1.2, 4.5, 6.8 and 7.4). In addition, based on the chemical structure of ceftazidime the order of ionization were suggested.
Keywords:
Ionization / Ceftazidime / Hyperquad
Source:
PHYSICAL CHEMISTRY 2022, 16th International Conference on Fundamental and Applied Aspects of Physical Chemistry (Proceedings), 2022, II, 585-588
Publisher:
Society of Physical Chemists of Serbia
Funding / projects:
The Ministry of Education, Science and Technological Development of the Republic of Serbia (grant no 452-03-9/2020-14/200014-0902105)
Note:
16th International Conference on Fundamental and Applied Aspects of Physical Chemistry, September 26-30, 2022
Belgrade, Serbia
TY - CONF
AU - Popović-Nikolić, Marija
AU - Mudrić, Jelena
AU - Popović, Gordana
PY - 2022
UR - https://farfar.pharmacy.bg.ac.rs/handle/123456789/4683
AB - The ionization constants (pKa) of ceftazidime, third generation cephalosporin, were determined by potentiometry. Ceftazidime is an ampholyte with four ionizable centers, three acidic centers (two carboxyl groups and amide group) and one basic center (aminothiazole). Potentiometric determinations were performed at 25 °C and constant ionic strength of 0.1 M (NaCl). Experimental data were analyzed by computer software Hyperquad and four pKa values were derived: pKa1 2.55; pKa2 3.94; pKa3 4.54 and pKa4 7.55. According to the obtained pKa values distribution diagram as a function of pH was constructed and distribution of the ceftazidime equilibrium forms was calculated at a pH values of biopharmaceutical significance (pH 1.2, 4.5, 6.8 and 7.4). In addition, based on the chemical structure of ceftazidime the order of ionization were suggested.
PB - Society of Physical Chemists of Serbia
C3 - PHYSICAL CHEMISTRY 2022, 16th International Conference on Fundamental and Applied Aspects of Physical Chemistry (Proceedings)
T1 - The determination of the ionization profile of ceftazidime
VL - II
SP - 585
EP - 588
UR - https://hdl.handle.net/21.15107/rcub_farfar_4683
ER -
@conference{
author = "Popović-Nikolić, Marija and Mudrić, Jelena and Popović, Gordana",
year = "2022",
abstract = "The ionization constants (pKa) of ceftazidime, third generation cephalosporin, were determined by potentiometry. Ceftazidime is an ampholyte with four ionizable centers, three acidic centers (two carboxyl groups and amide group) and one basic center (aminothiazole). Potentiometric determinations were performed at 25 °C and constant ionic strength of 0.1 M (NaCl). Experimental data were analyzed by computer software Hyperquad and four pKa values were derived: pKa1 2.55; pKa2 3.94; pKa3 4.54 and pKa4 7.55. According to the obtained pKa values distribution diagram as a function of pH was constructed and distribution of the ceftazidime equilibrium forms was calculated at a pH values of biopharmaceutical significance (pH 1.2, 4.5, 6.8 and 7.4). In addition, based on the chemical structure of ceftazidime the order of ionization were suggested.",
publisher = "Society of Physical Chemists of Serbia",
journal = "PHYSICAL CHEMISTRY 2022, 16th International Conference on Fundamental and Applied Aspects of Physical Chemistry (Proceedings)",
title = "The determination of the ionization profile of ceftazidime",
volume = "II",
pages = "585-588",
url = "https://hdl.handle.net/21.15107/rcub_farfar_4683"
}
Popović-Nikolić, M., Mudrić, J.,& Popović, G.. (2022). The determination of the ionization profile of ceftazidime. in PHYSICAL CHEMISTRY 2022, 16th International Conference on Fundamental and Applied Aspects of Physical Chemistry (Proceedings)
Society of Physical Chemists of Serbia., II, 585-588.
https://hdl.handle.net/21.15107/rcub_farfar_4683
Popović-Nikolić M, Mudrić J, Popović G. The determination of the ionization profile of ceftazidime. in PHYSICAL CHEMISTRY 2022, 16th International Conference on Fundamental and Applied Aspects of Physical Chemistry (Proceedings). 2022;II:585-588.
https://hdl.handle.net/21.15107/rcub_farfar_4683 .
Popović-Nikolić, Marija, Mudrić, Jelena, Popović, Gordana, "The determination of the ionization profile of ceftazidime" in PHYSICAL CHEMISTRY 2022, 16th International Conference on Fundamental and Applied Aspects of Physical Chemistry (Proceedings), II (2022):585-588,
https://hdl.handle.net/21.15107/rcub_farfar_4683 .
