RESUMO
AIM To study the pharmacokinetics and bioavailability of clinafloxacin in rats. METHODS The drug concentration was determined by HPLC. The main pharmacokinetic parameters were obtained by 3P87 program. An RP-C18 was used as the stationary phase. The mobile phase was a mixture of acetonitrile-0.05 mol*L-1 citric acid triethylamine (pH 2.5) (20∶80). The flow rate was 1.0 mL*min-1. The UV absorbance detector was set at 300 nm. RESULTS A good linearity was obtained from 0.03-20 μg*mL-1 of clinafloxacin in rat plasma with γ=0.9998. The plasma concentration-time curve of clinafloxacin conformed to one compartment open model. After ig administration of 50 mg*kg-1 and 100 mg*kg-1 dose of clinafloxacin in six rats, mean Cmax and AUC values increased in proportion to dose. Mean T1/2 appeared to be independent of dose. Mean AUC was 65±6 and 27±4 μg*h*mL-1 respectively after iv and ig adminostration of 100 mg*kg-1 dose. The extent of bioavailability (F) of clinafloxacin was 42%. CONCLUSION The results of the pharmacokinetic study of clinafloxacin showed that it exhibited first order kinetic characteristics and the bioavailability is low.