Fluorescence probe enhanced spectrofluorimetric method for the determination of gatifloxacin in pharmaceutical formulations and biological fluids

A spectrofluorimetry for the determination of gatifloxacin (GFLX) was developed based on the strong fluorescence of gatifloxacin after adding fluorescence probe yttrium in buffer solution (pH 7.0) and various factors of influencing fluorescence have been researched. Under the optimum conditions, the liner range was 4.00 × 10−8 to 1.00 × 10−6 g mL−1 and the detection limit is 3.36 × 10−9 g mL−1 (correlation coefficient r = 0.9997), respectively. The relative standard deviation was 1.1% for 11 measurements of 5.6 × 10−7 g mL−1 gatifloxacin standard solution. The mechanism of sensitizing effect of probe was discussed. The proposed method has been successfully applied to determine real samples and the obtained results are in good agreement with the results of HPLC.