#36 Development and validation of analytical method for simultaneous estimation of Telmisartan and Gallic acid by RP-HPLC

Abstract

A simple, sensitive, rapid, reliable, and economic RP-HPLC method was developed & validated for simultaneous estimation of Telmisartan and gallic acid in bulk and a pharmaceutical dosage form. One of the prominent causes of hypertension is oxidative stress produced by reactive oxygen species. Gallic acid is a polyphenolic drug, having a very good antioxidative property that reduces oxidative stress. Telmisartan is a well-known AT1 receptor blocker and comparatively safer among all antihypertensive drugs. Combined administration of both drugs will produce a synergistic effect against hypertension. This study gives an opportunity for standardization of combined formulation. Telmisartan and gallic acid were chromatographed by RP-HPLC Waters-1525 binary pump, C-18 Column (length- 250 mm, internal diameter- 4 mm, particle size- 5 µm) with mobile phase: methanol: water (60:40, pH – 3.5 adjusted by acetic acid). Sample prepared with the mobile phase. Flow rate: 1 mL/min., run Time: 12 min., injection volume: 20 µL, detection, and quantification were performed by using a deuterium lamp operated by BREEZE software. a very good resolution was observed at λ = 273 nm for both of the drugs. Calibration plots were established showing the dependence of response on the amount chromatographed. The linear regression analysis data for the calibration plots showed good linear relation with R²= 0.998 for peak area of both the drugs between concentration range of 5 50 µg/mL. For gallic acid Rt - 2.757 min, LOD- 1.045 µg/mL, LOQ- 3.167 µg/mL and for Telmisartan Rt - 7.910 min, LOD- 1.004 µg/mL, LOQ- 3.044 µg/mL respectively. The method was validated as per ICH guidelines & can be adopted to validate and standardize other related pharmaceutical products.