Development and validation of a UV spectrophotometric method for thesimultaneous determination of ciprofloxacin hydrochloride and metronidazole in binary mixture

Marianne Alphonse Mahrouse

Abstract

A new, simple, accurate and sensitive UV spectrophotometric method was adopted and validated for the quantitative determination of ciprofloxacin hydrochloride (CIP) and metronidazole (MET), simultaneously, either in pure form or in pharmaceutical dosage form. Second derivative ratio spectrophotometry technique (2DD) was applied, by measuring the amplitude of the maximum at 253 nm, using a normalized spectrum of MET as divisor, for the determination of CIP. MET was quantified by measuring the amplitude of the minimum at 301 nm, using the normalized spectrum of CIP as divisor. Linearity was obtained over the concentration range 2 – 16 μg mL-1 and 4 – 16 μg mL-1, for CIP and MET, respectively. Mean percentage accuracy was found to be 100.39 ± 0.677 and 100.21 ± 0.982, for CIP and MET, respectively. The proposed procedure was successfully applied for laboratory prepared mixtures without prior separation. The percentages recoveries of CIP and MET in tablet were more than 98%. The method was validated in respect to linearity, accuracy, precision and limit of detection and that of quantification, which prove suitability of the developed method for the routine estimation of both drugs in bulk powder and solid dosage form.