Determination of cefazedone in human plasma by high performance liquid chromatography-tandem mass spectrometry: Application to a pharmacokinetic study on Chinese volunteers.

A rapid, sensitive and simple high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for determination of cefazedone in human plasma using metronidazole as internal standard (IS). The chromatographic separation was achieved on an Ultimate XB-CN column (2.1mm×150mm, 5μm) with an isocratic mobile phase of acetonitrile and 20mM ammonium acetate in 0.1% formic acid in water (15:85, v/v). Detection was performed using electrospray ionization in positive ion multiple reaction-monitoring mode (SRM), monitoring the transitions m/z 548.2→344.1 for cefazedone and m/z 172.2→128.1 for IS. Calibration curves were linear over a wide range of 0.20-401.12μg/mL for cefazedone in plasma. The lower limit of quantification (LLOQ) was 0.20μg/mL. The intra- and inter-day precisions were less than 7.2%. The average recovery of cefazedone was 90.8-91.0%. The validated method was successfully applied to the pharmacokinetic study of cefazedone in Chinese healthy volunteers following intravenous (IV) administration of 500, 1000 and 2000mg cefazedone injection.