Simultaneous determination of Nitazoxanide and Ofloxacin in pharmaceutical preparations using UV-spectrophotometric and high performance thin layer chromatography methods

Simple, precise, and accurate UV-Spectrophotometric and high-performance thin-layer chromatography (HPTLC) methods for the simultaneous determination of Nitazoxanide and Ofloxacin in pharmaceutical preparations have been developed and validated. The method was developed using aluminum plates pre-coated with silica gel 60 F254 HPTLC plates as a stationary phase with toluene:chloroform:carbon tetra chloride:toluene:glacial acetic acid solutions in the proportion of (10:5:3:0.5 v/v/v/v) as mobile phase. Densitometric quantification was performed at 241 nm. Well-resolved bands were obtained with RF values 0.36, 0.57 and 0.63 for Rosiglitazone maleate, Nitazoxanide, and Ofloxacin, respectively. Rosiglitazone maleate was used as an internal standard. The calibration curves were linear within the concentration range of 5-25 μg/ml for each drug. Two simple spectrophotometric methods have been developed for simultaneous estimation of Nitazoxanide, and Ofloxacin from tablet dosage form. The first method, simultaneous equation method, involves the measurement of absorbances at two wavelengths 221.8 nm (λmax of Nitazoxanide) and 244.3 nm (λmax of Ofloxacin), and the second method is First order derivative spectroscopy, wavelengths selected for quantitation were 263.6 nm for Nitazoxanide and 269.2 nm for Ofloxacin. The proposed method gave good validation results and the statistical analysis performed proved that the method is precise, accurate and reproducible, and hence can be employed for routine analysis of Nitazoxanide and Ofloxacin in bulk and commercial formulations.