Development and validation of a MEKC method for the direct determination of cefozopran in human serum.
A method for determining the concentration of cefozopran, a cephem anti-microbial agent which has a broad spectrum, in human serum using micellar electrokinetic capillary chromatography (MEKC) by serum direct injection is developed and the validation of the assays of this method is performed. A borate buffer (25mM; pH 10.0) containing sodium dodecyl sulfate (SDS) (50mM) is used as a run buffer. The electrophoresis of serum samples is carried out at 25kV and the detection of cefozopran at 244nm as its absorption maximum at the cathodic side of the capillary. The migration time of cefozopran is 6.5min. Linearity (0-200mg/l) is good and limit of quantification is 0.5mg/l at a signal-to-noise ratio of 3. Coefficient of variation (CV) of intra-day precision and that of inter-day precision are 2.4-4.0% (7.3-92.0mg/l) and 2.9-7.7% (22.5-71.4mg/l), respectively, and the recovery rate is 92-109%. The detection results of 12 other cephem anti-microbial agents under the analytical conditions of this method show that the migration time of cefmetazole is identical with that of cefozopran, making it impossible to separate these two anti-microbial agents. This method is characterized by the fact that simple and economic determination can be achieved by directly injecting the serum samples of micro-quantities into the capillary.
Kitahashi
Toshihiro
T
Department of Laboratory Medicine, Kinki University School of Medicine, 377-2 Ohno-higashi, Osakasayama, Osaka, Japan. kitahasi@med.kindai.ac.jp
Furuta
Itaru
I
D002511:Cephalosporins / Q000097:blood* / Q000737:chemistry; D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods* / Q000592:standards; D006801:Humans; D044967:Serum / Q000737:chemistry*; D000097586:Cefozopran
D002511:Cephalosporins; D000097586:Cefozopran