Abstract

A new rapid, sensitive, simple, and cost-effective spectrofluorimetric method was developed for the estimation of gatifloxacin in bulk and pharmaceutical formulations. The relative fluorescence intensity of gatifloxacin in 10 mM hydrochloric acid (pH 2.0) was measured at excitation wavelength (λexc ) of 292 nm and emission wavelength (λem ) of 482 nm. Linearity range was found to be 20-160 ng/ml with regression equation, relative fluorescence intensity = 36.05 ´ concentration in ng/ml + 12.60 with regression coefficient (r ²) = 0.9998. The method was tested and validated for various parameters according to ICH guidelines and USP. The detection and quantitation limits were found to be 5.48 and 16.61 ng/ml, respectively. The results demonstrated that the procedure is accurate, precise, and reproducible (relative standard deviation <2%), while being simple and less time consuming. The method is applicable for the estimation of gatifloxacin in different dosage forms and the results are in good agreement with label claims.