Comparative study of new spectrophotometric methods; An application on pharmaceutical binary mixture of ciprofloxacin hydrochloride and hydrocortisone

Abstract

Simple, specific, accurate and precise spectrophotometric methods were developed and validated for simultaneous estimation of Ciprofloxacin hydrochloride (CIP) and Hydrocortisone (HYD) in their pure form and pharmaceutical dosage form. Two new spectrophotometric methods were applied: extended ratio subtraction (EXRSM) and ratio difference (RDSM) methods. The results were compared to three well-established methods: Mean centering of ratio spectra method (MCR), Isoabsorpative point spectrophotometric method (IsoM) and Absorbance ratio method (ARM). The linearity range for the spectrophotometric methods was found to be (2-14 ?g/mL) and (1-14 ?g/mL) for CIP and HYD respectively. The selectivity of the developed methods was investigated by analyzing laboratory prepared mixtures of the two drugs and their combined dosage form. The results obtained from the proposed methods were statistically compared using one-way analysis of variance (ANOVA) where no significant difference was observed between the new (EXRSM and RDSM) and the well-established methods which prove their validity for the analysis of this binary mixture. The methods were validated as per ICH guidelines regarding accuracy, precision, repeatability and robustness; which were found to be within the acceptable limits. The new methods were simple, sensitive and don't need a special program, so they could be easily applied as alternative methods to LC methods in quality control laboratories lacking the required facilities for those techniques.