Application of Validated HPTLC Method for Dissolution Study of FDC Tablets Containing Telmisartan and Hydrochlorothiazide

A simple, selective, precise and HPTLC method for simultaneous determination of telmisartan and hydrochlorothiazide in the bulk drugs and in their fixed dose combination tablets (FDC) was developed and validated. The method was further applied in the dissolution study of formulated and marketed tablets containing these two drugs. The method employed HPTLC aluminium plates precoated with silica gel 60 F₂₅₄ as the stationary phase. The solvent system consisted of toluene-ethyl acetate-methanol-glacial acetic acid, 6: 3: 1: 0.5 (v/v). The detection was performed at 272 nm. The R_F values were 0.70 ± 2 for telmisartan and 0.44 ± 2 for hydrochlorothiazide. The linear relationships were obtained between peak area and amount of drugs in the range of 1-1000 ng spot^-1 with correlation coefficient of 0.9992 for telmisartan and 0.9994 for hydrochlorothiazide. The method was validated for precision, robustness and recovery. The limits of detection and quantification were 15.54 and 48.44 ng spot^-1 for telmisartan and 10.22 and 35.68 ng spot^-1 for hydrochlorothiazide, respectively. Invitro drug release from prepared tablets showed better drug release when compared with marketed tablets.