Determination of dissociation constants of cephalosporins by capillary zone electrophoresis

被引：70

作者：

Mrestani, Y

Neubert, R

Munk, A

Wiese, M

机构：

[1] Martin Luther Univ, Inst Pharmaceut & Biopharmaceut, D-06120 Halle, Germany

[2] Martin Luther Univ, Inst Pharmaceut Chem, D-06120 Halle, Germany

来源：

JOURNAL OF CHROMATOGRAPHY A | 1998年 / 803卷 / 1-2期

关键词：

dissociation constants; pharmaceutical analysis; cephalosporins; antibiotics;

D O I：

10.1016/S0021-9673(97)01213-2

中图分类号：

Q5 [生物化学];

学科分类号：

071010 ; 081704 ;

摘要：

Although the cephalosporins are important drugs in medical and in pharmaceutical research, the pK(a) of these substances is frequently not known. Dissociation constants of cephalosporins were determined by capillary zone electrophoresis (CZE) as a new technique and potentiometric titration (PMT) at low solute concentrations. The CZE method relies on measuring the ionic mobility of the solute as a function of pH. Mobility and pH data are fitted to an equilibrium expression by using nonlinear regression. The total analysis time for the determination of the pK(a) using CZE was 40 min. Potentiometric titration was performed as a comparative method to CZE for the determination of the dissociation constants. The total analysis time was 50 min and the sample concentration was between 200 and 300 mu g/ml. (C) 1998 Elsevier Science.

引用

页码：273 / 278

页数：6

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