Determination of prulifloxacin active metabolite in human plasma and urine by RP-HPLC / 中国感染与化疗杂志

ABSTRACT

Objective To establish a RP-HPLC method for determining the concentration of prulifloxacin active metabolite in human plasma and urine.Methods The supernatant obtained by centrifugation after the sample was precipitated with methanol- acetonitrile (1:1) was chromatographically separated on a Diamonsil C_(18)(250 mm?4.6 mm,5?m) using a mobile phase con- sisting of acetonitrile and 0.05 mol/L potassium dihydrogen phosphate (pH2.2) containing 1% tetrabutylammonium bromide. The solutions of 20:80 (V/V) and 12:88 (V/V) at a flow rate of 1.0 mL/min and 1.6 mL/min were used for plasma and u- rine, respectively.Then the samples were assayed at wavelength of Ex 280 nm and Em 425 nm.Results The linear range for prulifloxacin active metabolite in plasma and urine were 0.005-5 mg/L (r=0.9999) and 0.05-5 mg/L(r=0.9999)with a low- er limit of quantitation of 0.002 mg/L and 0.01 rag/L, respectively.In plasma, the relative recovery ranged from 100.64% to 101.00% at the concentration of 5.00, 0.50 and 0.05 mg/L and within-day and between-day precisions were less than 2.5% and 4.6% respectively.Meanwhile, the relative recovery ranged from 97.20% to 100.20% at the concentration of 2.50, 0.50 and 0.10 mg/L in urine.The within-day and between-day precisions were lower than 1.3% and 4.3%, respectively.The method had been successfully used for the pharmacokinetic studies of a prulifloxacin formulation after oral administration to healthy volunteers.Conclusions The present method is simple, rapid, accurate, reproducible and suitable for the pharmacoki- netic study of prulifloxacin in humans.