An Improved Validated UPLC Method for Separation of Losartan Potassium, Amlodipine and Hydrochlorothiazide impurities in Losartan Potassium, Amlodipine and Hydrochlorothiazide Tablets

A rapid, specific, sensitive Ultra-performance liquid chromatographic method has been developed for determination of Losartan Potassium, Amlodipine and Hydrochlorothiazide impurities and its degradation products in pharmaceuticals preparation. 16 impurities including degradation as well as process related impurities have been well separated. UPLC was performed on a C18 column with “mobile phase A” consisting of 90:10:0.1 v/v/v of water, Acetonitrile and TFA; while “mobile phase B” consisted of 10:90:0.1v/v/v of water, Acetonitrile and TFA. The mobile phase was pumped in a gradient manner at the flow-rate of 0.35 mL min−1. Ultraviolet detection was performed at 238 nm. Losartan Potassium, Amlodipine and Hydrochlorothiazide and its degradation products along with process impurities were chromatographed with a total run time of 20 minutes. Calibration showed that response of impurities was a linear function of concentration over the range LOQ to 150% of the target concentration (r 2≥0.999) and the method was validated over this range for precision, accuracy, linearity and specificity. For precision study, percentage relative standard deviation of each impurity was