Comparison of bioassay and HPLC for the determination of levofloxacin in plasma / 中国药学杂志

ABSTRACT

OBJECTIVE:The bioassay and HPLC methods were established and compared for the determination of levofloxacin(Lev) in human plasma.METHOD:In bioassay,medium Ⅱ and staphylococcus aureus were used.The HPLC method was chromatographed with a mobile phase of methanol-0.02mol/L potassium dihydrogen phosphate solution (3∶7)，the sample was treated by adding 30% trichloroacetic acid to precipitate protein,and detected at 276mm.RESULTS:The average recovery of bioassay was within 95.90%～106.68%,the within-day and day-to-day precisions were below 6%.The average recovery of HPLC was within 97.24%～101.70%,the within day and day-to-day precisions were blow 5%.Lev tablets were given to 6 patients in two ways.Drug concentrations in plasma were determined by bioassay and HPLC assay,respectively,with no significant difference (P＞0.05).CONCLUSION:The bioassay was simple,cheap,time saving,and reliable.The HPLC method wsa rapid,sensitive,accurate.The two methods may be selected to use in actual conditions.