New Ecofriendly Validated Spectrophotometric Method For The Estimation Of Amlodipine Besylate In Bulk Drug Using Ninhydrin

A new, accurate, precise and economical spectrophotometric method has been developed and validated for the determination of Amlodipine Besylate in bulk drugs. This method is based on the reaction of ninhydrin with primary amine present in the Amlodipine Besylate in the presence of Sodium Bicarbonate. This reaction proceeds quantitatively at 97 ± 1°C in 15 min and produces a purple color product which absorbs maximally at about 566 nm. Beer-Lambert’s law is obeyed in the concentration range of 50-250μg/ml and is described by the regression equation Y = 0.700x - 0.20 with a regression coefficient (r2) = 0.999 (n = 6). The effects of variables such as temperature, heating time, concentration of colour producing reagent and stability of colour were investigated to optimize the procedure. For Amlodipine Besylate, the value of molar absorptivity and Sandell’s sensitivity are 3.1077 x 103 L/mol/cm and 0.1824μg/cm2, respectively and of LOD and LOQ are found to be 0.09 and 0.2729μg/ml, respectively. The statistically validated results indicate that the proposed method has good sensitivity, accuracy, precision and stability. The method is eco friendly and economic as it does not involve a any organic solvents.