Simultaneous determination of related substances of telmisartan and hydrochlorothiazide in tablet dosage form by using reversed phase high performance liquid chromatographic method.

OBJECTIVE: Telmisartan is a potent, long-lasting, nonpeptide antagonist of the angiotensin II type-1 (AT(1)) receptor that is indicated for the treatment of essential hypertension. Hydrochlorothiazide is a widely prescribed diuretic and it is indicated for the treatment of edema, control of essential hypertension and management of diabetes insipidus. In the current article a new, accurate, sensitive, precise, rapid, reversed phase high performance liquid chromatography (RP-HPLC) method was developed for determination of related substances of Telmisartan and Hydrochlorthiazide in tablet dosage form.

MATERIALS AND METHODS: Simultaneous determination of related substances was performed on Kromasil C(18) analytical column (250 × 4.6 mm; 5μm pertical size) column at 40°C employing a gradient elution. Mobile phase consisting of solvent A (solution containing 2.0 g of potassium dihydrogen phosphate anhydrous and 1.04 g of Sodium 1- Hexane sulphonic acid monohydrate per liter of water, adjusted to pH 3.0 with orthophosphoric acid) and solvent B (mixture of Acetonitrile: Methanol in the ratio 80:20 v/v) was used at a flow rate of 1.0 ml min(-1). UV detection was performed at 270 nm.

RESULTS: During method validation parameter such as precision, linearity, accuracy, specificity, limit of detection and quantification were evaluated, which remained within acceptable limits.

CONCLUSIONS: HPLC analytical method is linear, accurate, precise, robust and specific, being able to separate the main drug from its degradation products. It may find application for the routine analysis of the related substances of both Telmisartan and Hydrochlorthiazide in this combination tablets.