Determination of binding constants of 5-phenylazopyrimidines with β-cyclodextrin by affinity capillary electrophoresis

0538657 - ÚOCHB 2021 CZ eng A - Abstract
Štěpánová, Sille - Procházková, Eliška - Čechová, Lucie - Janeba, Zlatko - Kašička, Václav
Determination of binding constants of 5-phenylazopyrimidines with β-cyclodextrin by affinity capillary electrophoresis.
Czech Chemical Society Symposium Series. Roč. 18, č. 3 (2020), s. 83-84. ISSN 2336-7202.
[Sjezd českých a slovenských chemických společností /72./. 06.09.2020-09.09.2020, Praha]
R&D Projects: GA ČR(CZ) GA18-02597S
Institutional support: RVO:61388963
Keywords : affinity capillary electrophoresis * binding constant * 5-phenylazopyrimidines
OECD category: Analytical chemistry
https://sjezd72.csch.cz/wp-content/uploads/2020/09/Sjezd-Praha-2020-tisk.pdf

Non-covalent molecular interactions play important role in all living systems being essential to many chemical or biochemical processes. For characterization of these interactions, among other methods, also various modes of affinity capillary electrophoresis (ACE) have been employed. In this study, strength of non-covalent interactions of two 5 phenylazopyrimidines1 (see Fig. 1), with β-cyclodextrin (β CD) were estimated by mobility shift ACE (ms-ACE)2 . During ms-ACE measurements, 5-phenylazopyrimidines were dissolved in background electrolyte (BGE) free of β-CD, and injected as analytes. β-CD at various concentrations (0– 15 mM) was added to the BGE (18.5/42 mM Tris/H3PO4, pH 2.3). For 5-phenylazopyrimidines complexes with β-CD, 1:1 stoichiometry ratio was assumed. From the measured migration times, the effective mobilities of analytes were calculated and plotted against β-CD concentration in the BGE. For calculation of the apparent binding constant, a nonlinear regression analysis was applied. The apparent binding constants of complexes of compounds 1 and 2 with β-CD were estimated to be 22.9 ± 2.9 L/mol and 98.9 ± 3.6 L/mol, respectively.
Permanent Link: http://hdl.handle.net/11104/0316947