Development and Validation of Stability Indicating HPTLC and HPLC Methods for Simultaneous Determination of Telmisartan and Atorvastatin in Their Formulations

The present study describes development and subsequent validation of stability indicating HPLC and HPTLC methods for simultaneous estimation of Telmisartan (TLM) and Atorvastatin (ATV) in their combined formulation. The proposed RP-HPLC method utilizes a Phenomenex Luna C-18 column using acetonitrile: 0.025Mammoniumacetate (38 : 52%, v/v) as mobile phase (pH 3.8), flow rate of 1.0 mL/min. Quantification was achieved with UV detection at 281 nm over concentration range of 12 to 72 mu g/mL for TLM and 3 to 18 mu g/mL for ATV respectively. In HPTLC, separations were performed on silica gel 60 F-254 using toluene-methanol-ethyl acetate-acetic acid (5 : 1 : 1 : 0.3, v/v) as mobile phase. The compact bands of TLM and ATV at R-f 0.37 +/- 0.02 and 0.63 +/- 0.01 respectively were scanned at 279 nm. Linear regression analysis revealed linearity in the range of 40 to 240 ng/band for TLM and 10 to 60 ng/band for ATV respectively. For both the methods, dosage form was exposed to thermal, photolytic, acid, alkali and oxidative stress. The methods distinctly separated the drugs and degradation products even in actual samples. In conclusion, the proposed HPLC and HPTLC methods were appropriate for routine quantification of TLM and ATV in tablet formulation.