Chromatography Technique

A simple, precise, accurate and reproducible high performance liquid chromatography method was developed for the simultaneous quantitative determination of antihypertensive drugs Losartan and Chlorthalidone from their combined drug product. The separation was achieved by a simple isocratic method using phenomenex C18 column. The mobile phase contains a mixture of acetonitrile and water in the ratio 80:20%v/v at a flow rate of 1.0 mL min−1 and the column was maintained at normal temperature. The detector wavelength was 284 nm. The retention times of Losartan and Chlorthalidone were 1.72 minutes and 2.64 minutes respectively with a total runtime of 10 minutes. The described method was validated with respect to system suitability, specificity, linearity, precision and accuracy. A low percentage RSD indicated the method was accurate and precise and can be used for the quantification of these drugs in

Assay of market formulation

20 tablets were accurately weighed and crushed into a fine powder. The powder equivalent to 50 mg was taken in 100 ml volumetric flask. About 50 ml methanol was added and then sonicated for 8 mins.Then the volume was finally made up to the mark (100ml).The solution was filtrated through whatmann filter paper. Then 0.6 ml of solution was further diluted to 10ml with mobile phase to get final sample concentration. Standard and sample solutions were injected five times and respectively to get the chromatograms.

RESULT AND DISCUSSION:

To develop a precise, accurate and suitable RP- HPLCmethod for the simultaneous estimation of Losartan and Chlorthalidone,different mobile phases were tried and the proposedchromatographic conditions were found to be appropriatefor the quantitative