Abstract
Three simple, specific, accurate and precise spectrophotometric methods are developed for simultaneous determination of amlodipine besylate (AM) and atenolol (AT) in tablets. The first method is dual wavelength spectrophotometry (DW). The second method is ratio subtraction (RS) which depends on subtraction of the plateau values from the ratio spectrum, coupled to first derivative of ratio spectra (1 DD). The third method applies bivariate calibration method using 210 and 225 nm as an optimum pair of wavelength for amlodipine and atenolol. The calibration curves are linear over the concentration range of 4 similar to 40 mu g . mL(-1) for both drugs. The specificity of the developed methods is investigated by analyzing laboratory prepared mixtures of the two drugs and their combined dosage form. The two methods are validated as per ICH guidelines and can be applied for routine quality control testing.