Tablets.

A simple, specific, accurate and precise reverse phase high performance liquid chromatographic method was developed and validated for the estimation of Venlafaxine hydrochloride in pure and Pharmaceutical dosage form. Kromasil C18 column having 150 mm x 4.6 mm internal diameter, 5 µm particle sizes in isocratic mode with mobile phase containing mixture of methanol and water in the ratio of 65:35 v/v was used. The flow rate was 1.0 ml/min and effluents were monitored at 225 nm. The retention time for Venlafaxine was 2.424 min. The method was validated for linearity, accuracy, precision, specificity, limit of detection, limit of quantification and robustness. Limit of detection and limit of quantification were found 2.97µg/ml and 9.92 µg/ml respectively and recovery of Venlafaxine from tablet formulation was found 100.4 %. The proposed method was successfully applied for the quantitative determination of Venlafaxine in tablet dosage form.

A reverse phase HPLC method is developed for the determination of Azilsartan medoximil and chlorthalidone in pharmaceutical dosage forms. Chromatography was carried out on a C18 column 4.6 x 100mm, 5µm, Make: BDS using a mixture of potassium Di hydrogen ortho phosphate buffer and acetonitrile (35:65 v/v) as the mobile phase at a flow rate of 1.0 ml/min. Detection was carried out at 273 nm . The retention time of Azilsartan Medoxomil and Chlorthalidone was 2.59±0.1 mins and 3.85±0.5 min respectively. The linearity was observed In range of 2.5-15 µg/ml and 10-60 µg/ml with a correlation coefficient of Azilsartan medoximil and chlorthalidone were 0.996 and 0.999.the proposed method was validated for its linearity, accuracy, precision and robustness. The proposed method was found to be simple, rapid, accurate and precise. It was found to be economical and suitable for simultaneous determination of Azilsartan Medoxomil and Chlorthalidone in pharmaceutical dosage form.

In this study, a simple, sensitive and highly accurate ultraviolet spectrophotometric method has been developed and validated for determination of atenolol in bulk and pharmaceutical formulations. The method is based on the measurement of the absorbance of atenolol solution in methanol: phosphate buffer pH 6.8 (10:90) at 224 nm in the wavelength range of 200 - 400 nm. Beer’s law was obeyed in the concentration range of 5-25 µg/mL. The slope, intercept and correlation coefficient were also calculated. Results of percentage recovery shows that the method was not affected by the presence of common excipients in tablets. The developed method was validated in terms of accuracy, precision, linearity, limit of detection, limit of quantification which proves suitability of proposed method for routine estimation of atenolol in bulk and pharmaceutical formulations.