Simultaneous spectrophotometric estimation of Amlodipine Besylate and Benazepril HCl in pure and pharmaceutical dosage form

Two simple, accurate, precise, reproducible, requiring no prior separation and economical procedures for simultaneous estimation of amlodipine besylate and benazepril HCl in capsule dosage form have been developed. First method is simultaneous equation method; in this method 366 nm and 238 nm were selected to measure the absorbance of drugs at both wavelengths. The second method is Q-value analysis based on measurement of absorbance at 213 nm (as an iso-absorptive point) and 238 nm (l max of benazepril HCl). At selected wavelength both drugs show linearity in a concentration range of 10A±50 μm/ml. Both methods are validated as per ICH guideline. The proposed methods are recommended for routine analysis since it is rapid, simple, accurate, and sensitive and specific as it does not required heating and organic solvent for extraction.