Abstract
A simple and precise stability indicating RP-HPLC method was developed and validated for simultaneous determination of Quinapril and Hydrochlorothiazide in pure drug and Pharmaceutical marketed formulation. Chromatography was carried out on Hypersil ODS C18 (150 x 4.6 mm, 5 particle size) column in an isocratic mode with mobile phase containing phosphate buffer (adjusted to pH 4.8 with dilute orthophosphoric acid) and acetonitrile in the ratio of 45:55% v/v at a flow rate of 0.9 ml/min. The analyte was monitored using PDA detector at 210 nm. The retention time was found to be 2.214 min and 3.942 min for Hydrochlorothiazide (HCTZ) and Quinapril respectively. The proposed method was found to be having linearity in the concentration range of 10-60 μg/ml for Quinapril and 12.5-75.0 μg/ml for Hydrochlorothiazide (HCTZ) with correlation coefficient value of 0.999 respectively. The mean % recoveries obtained were found to be 99.74-99.92 % for Hydrochlorothiazide (HCTZ) and 99.42-100.02 % for Quinapril respectively. Stress testing which covered acid, base, peroxide, UV light, neutral and thermal degradation was performed on under test to prove the specificity of the method and the degradation was achieved. The developed method has been statistically validated according to ICH guide lines. Thus the proposed method can be successfully applied for the stability indicating simultaneous determination of Quinapril and Hydrochlorothiazide (HCTZ) in bulk and pharmaceuticals and in routine quality control analysis.
