Simultaneous UV Spectrophotometric Method for Estimation of Amlodipine Besylate and Lisinopril in Tablet Dosage Form

Two simple, accurate, precise, reproducible, requiring no prior separation and economical procedures for simultaneous estimation of Amlodipine Besylate and Lisinopril in tablet dosage form have been developed. First method employs formation and solving of simultaneous equation using 239 nm and 207 nm as two analytical wavelengths for both drugs in Triple distilled water. The second method is Q value analysis based on measurement of absorptivity at 212.5 nm (as an iso-absorptive point) and 239 nm. Amlodipine Besylate and Lisinopril at their respective λmax 239 nm and 207 nm and at isoabsorptive point 212.5 nm shows linearity in a concentration range of 5-30 μg/mL. Recovery studies range from 101.49% for Amlodipine Besylate and 99.27% for Lisinopril in case of simultaneous equation method and 100.76% for Amlodipine Besylate and 99.73% for Lisinopril in case of Q-analysis method confirming the accuracy of the proposed method. The proposed method is recommended for routine analysis since it is rapid, simple, accurate and also sensitive and specific.