Application of capillary zone electrophoresis to the analysis and to a stability study of cephalosporins

The applicability of capillary zone electrophoresis (CZE) for the determination of cephalosporin antibiotics has been studied. In the case of the separation conditions optimised for fourteen cephalosporins, the precision of migration times was smaller than 1.3% RSD, and the values of the limit of detection ranged between 0.42 and 1.62 μg/ml. The proposed CZE method was applied to study the stability of cephalosporins in water at different temperatures (+25, +4 and −18 °C). It was established that the degradation of most cephalosporins was not higher than 20% at room temperature within 4 h of dissolution of these antibiotics.