ABSTRACT:
A simple, selective, precise and stability-indicating high-performance thin- layer chromatographic (HPTLC) method for densitometric determination of telmisartan both as a bulk drug and in formulation was developed and validated as per the international conference on harmonization guidelines (ICH). The method employed TLC aluminium plates precoated with silica gel 60F-254 as the stationary phase. The solvent system comprised of ethyl acetate: dichloroethane: methanol (6:2:1 v/v). Densitometric analysis of telmisartan was carried out in the absorbance mode at 295 nm. The system was found to give compact spot for telmisartan (Rf value of 0.68 ± 0.03). The linear regression analysis data for the calibration plots showed good relationship with r2= 0.9997 ± 0.0002 in the concentration range 300 -1800 ng per spot. The mean value ± S.D. of slope and intercept were 10.111 ± 0.042 and 160.65 ± 21.84 with respect to peak area. The limit of detection (LOD) and limit of quantitation (LOQ) were 19.30 ng and 58.50 ng per spot, respectively. Telmisartan was subjected to acid and alkali hydrolysis, oxidation and thermal degradation and photo degradation. All the peaks of degradation products were well resolved from the standard drug with significantly different Rf values. Statistical analysis proves that the method is repeatable, selective and accurate for the estimation of said drug. The proposed developed HPTLC method can be applied for identification and quantitative determination of telmisartan in the bulk and dosage form.