DEVELOPMENT AND VALIDATION OF A HPLC METHOD WITH UV DETECTOR FOR QUANTIFICATION OF GEMIFLOXACIN IN HUMAN PLASMA: APPLICATION TO BIOEQUIVALENCE STUDY

A simple, sensitive, high throughput and specific HPLC method with UV detection was developed and validated to according to the FDA guideline for quantification of gemifloxacin in human plasma. The bioanalytical method consists of liquid-liquid extraction and quantification by UV detection. The analyte was separated isocratically on a Cyano column (250 X 4.6 mm, 5µ particle size) with a mobile phase consist of 1% v/v formic acid, acetonitrile and  methanol in the ratio of 75:20:5 (v/v). The response to gemifloxacin was linear over range 0.025 to 2.000 μg/mL. The validation results demonstrate that the method had satisfactory precession and accuracy across the calibration range. Intra-and inter-day precession range from 0.676 to 1.222 and from 0.834 to 1.645% (RSD), respectively. The accuracy determine at three quality control samples was within 94.232 to 101.132%. There was no evidence of instability of the analyte in human plasma following the stability study. The method proved highly reproducible and sensitive and was successfully applied in bioequivalence study after oral dosing of gemifloxacin tablet in human volunteer. This method may be applicable for gemifloxacin single and multi dose pharmacokinetic study, tissue distribution study toxicokinetic study and tissue distribution modeling study in lower mammals.