Stability Indicating Reverse Phase High Performance Liquid Chromatographic Method with Photodiode Array Detection for the Simultaneous Quantification of Quinapril and Hydrochlorthiazide in Bulk and Tablet Dosage Forms

摘要

The combination of hydrochlorothiazide and quinapril is used to treat high blood pressure. In the current study, a stability-indicating RP-HPLC method with photodiode array detection was developed and validated for the simultaneous determination of quinapril and hydrochlorthiazide in bulk and tablet dosage form. Separation and analysis of selected drug combination in the presence of degradation products was achieved on Agilent C_(18) (250 mm x 4.6 mm, 5 u) column. A mixture of 0.1 M KH2PO4 and methanol (65:35, v/v) was used as mobile phase. The developed method was linear over the concentration range of 10-30 μg/mL (quinapril) and 6.25-18.75 μg/mL (hydrochlorothiazide) with acceptable precision and accuracy. The degradation studies showed that quinapril and hydrochlorthiazide are relatively unstable under acidic, basic, oxidative, thermal and photo degradation conditions applied. No interference peaks from common tablet excipients and degradation products were observed. The proposed stability-indicating RP-HPLC method could be opt for routine quality control studies of quinapril and hydrochlorthiazide combined dosage forms.