Stability Indicating Validated HPLC Method for Simultaneous Quantification of Nitazoxanide and Ofloxacin in Pharmaceutical Dosage Form

A simple, rapid, and precise reverse phase HPLC method is developed for the simultaneous estimation of nitazoxanide (NTZ) and ofloxacin (OFN) in fixed dose combination product. Chromatographic separations of NTZ and OFN were achieved using C-8 (250.0 x 4.6 mm, 5 mu m) column and using mixture of phosphate buffer pH 7.0 and acetonitrile (70: 30, v/v) as mobile phase. The mobile phase was pumped at flow rate of 1.0 mL/min column oven temperature was set at 35 degrees C. Column effluents were monitor using photo diode array detector at wavelength of 254 nm. The stress degradation studies were performed on NTZ and OFN and their combination drug product under various stress conditions such as thermal, photolytic, hydrolytic and oxidative. The stress subject samples were analyzed by proposed method and able to separate the degradation products from the NTZ and OFN peak. The developed method is validated as per ICH Q2A (R1) found to be compliant all the parameters. The proposed method can be applied to quantify NTZ and OFN in the combination product such as tablet and stability studies of the same.