Novel spectrophotometric methods for the determination of fluconazole in the presence of its oxidative degradation product

Abstract

Five sensitive, selective and precise spectrophotometric stability-indicating methods for the determination of fluconazole in the presence of its oxidative degradation product and in pharmaceutical formulations are developed and validated. Method A is a newly developed spectrophotometric one that is called ratio difference method by measuring the difference in amplitudes between 261.5 and 266.5 nm of ratio spectrum. Method B is a third derivative spectrophotometric one, which determines peak amplitudes from 265.5-268nm (peak-peak). Method C is ratio subtraction method. Method D is the first derivative of the ratio spectra by measuring the peak amplitude at 269 nm. Finally, method E is the mean centering of ratio spectra method by measuring the peak amplitude at 266.5 nm. The proposed methods allow the determination of fluconazole in the presence of its oxidative degradation product over a concentration range of 50-400 μg.mL-1 with mean percentage recoveries of 100.24±0.91, 99.91±0.52, 100.20±1.26, 99.79±0.69, and 100.77±0.72 respectively. The selectivity of the proposed methods is checked using laboratory prepared mixtures. The proposed methods have been successfully applied to the analysis of fluconazole in pharmaceutical dosage forms without interference from other dosage form additives and the results have been statistically compared with a reported method.