Simultaneous determination of the antihypertensives hydrochlorothiazide,losartan potassium,irbesartan and valsartan in bulk powders and pharmaceutical preparations by high performance liquid chromatography

Abstract

A simple, rapid and accurate, routine-LC method is described for simultaneous determination of four antihypertensive drugs, hydrochlorothiazide, losartan potassium, valsartan and irbesartan in bulk powders and pharmaceutical preparations. The chromatographic separation of the four pharmaceuticals was achieved on a reversed phase C18 “Intersil^® ODS-3” column (5 μm, 4.6×250 mm) using a binary mobile phase of 45% ACN and 55% 50 mM KH₂PO₄ (pH 4.5) at 1 mL/min flow rate. The detection-wavelength was 210 nm. The total separation time was less than 12 min. The method was validated for system efficiency, linearity, accuracy, precision, limits of detection and quantitation, specificity, stability and robustness. The limits of detection were 0.02, 0.12, 0.14 and 0.01 μg/mL for hydrochlorothiazide, losartan potassium, valsartan and irbesartan, respectively. Linearity ranges were 5–50 μg/mL for hydrochlorothiazide, 10–100 μg/mL for losartan potassium, irbesartan and valsartan. The recovery values of this method were between 97 and 103% and the reproducibility was within 1.67%. Statistical analysis proved that the method enabled reproducible and selective quantification of all four analytes as the bulk drug and in pharmaceutical preparations.