NOVEL ISOCRATIC REVERSE PHASE HIGH PERFORMANCE LIQUID CHROMATOGRAPHY METHOD DEVELOPMENT AND VALIDATION FOR SIMULTANEOUS ESTIMATION OF CIPROFLOXACIN AND PHENAZOPYRIDINE IN SOLID DOSAGE FORM

Objective: To develop a new, simple, validated reverse phase high performance liquid chromatography (RP-HPLC) method for the simultaneous quantitative determination of Ciprofloxacin (CFX) and Phenazopyridine (PZD) in combined tablet dosage form.Methods: Simultaneous chromatographic separation and quantification of CFX and PZD was achieved using waters Alliance HPLC system on a C18 column (250 x 4.6 mm i. d, 5 μm particle size) maintained at ambient temperature in isocratic mode, with mobile phase comprising of ammonium ortho phosphate (0.01 N, pH 3.5 adjusted with dilute ammonia solution) and acetonitrile at the ratio of 50:50 (v/v) pumped on to the column at a flow rate of 1 ml/min followed by detection of eluents at isoabsorptivity wavelength of 275 nm within total run time was 8 min. Water and Acetonitrile in the ratio of 90:10 (v/v) were used as needle wash and the injection volume was 20 µl.Results: CFX and PZD have eluted with retention time (tr) of 2.783 min & 4.111 min, respectively and quantification permitted over a linear concentration range of 25-150 μg/ml, (R2 =1, Y= 23106 x+5020) & 10-60 μg/ml, (R2 =1, Y= 35116 x-900.36) respectively. The limits of detection and of quantification were 1.44 & 4.38 μg/ml for CFX and 0.964 & 2.92 μg/ml for PZD, respectively. % mean recoveries were ranging 99.29-100.57 % for CFX and 99.36-100.02 % for PZD respectively while, the relative standard deviation (% RSD) of intra-day and inter-day precision was 0.91 & 0.79, for CFX and 1.03 & 0.83, for PZD respectively. The specificity data of the proposed method indicated that excipients in the formulation did not interfere with the drug peaks of CFX and PZD. Furthermore, the well-shaped peaks buttressed the specificity of the method.Conclusion: The RP-HPLC method is simple, cost-effective and accurate for the simultaneous estimation of CFX and PZD in both bulk and pharmaceutical dosage form and it can be employed for routine laboratory analysis.Â