METHOD DEVELOPMENT AND VALIDATION FOR THE ESTIMATION OF TELMISARTAN AND CHLORTHALIDONE IN BULK AND IN PHARMACEUTICAL DOSAGE FORM BY RP-HPLC METHOD

A simple , fast, economic reverse phase high performance liquid chromatography (RP-HPLC) method has been developed and validated for simultaneous and quantitative analysis of telmisartan and chlorthalidone in commercial brand of ERITEL-CH40 (telmisartan 40 mg and chlorthalidone12. 5 mg). The method was developed using the mobile phase comprising of Acetonitrile : 0.01M Potassium-dihydrogen-phosphate buffer pH 4.0 and in the ratio of 65:35 (v/v), over the phenomenex C18 Gemini column (250X4.6mm, 5?m) at ambient temperature. The flow rate was at 1.0 ml/min, and the eluent was monitored by a PDA detector at 257nm. The total run time required was under 7.00mins. The linearity and range were established over the range of 20-100 μg/ml for telmisartan and 6.25-31.25 ?g/ml for chlorthalidone. The correlation coefficient of telmisartan and chlorthalidone was found to be 0.9998 and 0.9995. The method has been validated for accuracy, precision, and system suitability. The percentage recoveries were found to be 100.12-100.52% for telmisartan and 99.73-99.94% for chlorthalidone demonstrative of accuracy of the protocol. The low standard deviation values and good recoveries indicate the reproducibility and accuracy of the developed method. As well the % RSD values for precision study also were within acceptable limits.