Simultaneous Spectrophotometric Estimation of Telmisartan and Amlodipine in Tablet Dosage Form

Four new simple, accurate and precise spectrophotometric methods have been developed for simultaneous determination of telmisartan and amlodipine in pharmaceutical dosage form. Method A involves formation and solving of simultaneous equation using 299nm and 364nm as two wavelengths. Method B involves formation of Q-absorbance equation at 339nm (iso absorptive point) and at 299nm (λ max of telmisartan). Method C involves first order derivative method for simultaneous estimation of these two drugs. Method D involves the AUC for first order derivative spectrum. Both the drugs obey the Beer's law in the range 5-50μg/mL for amlodipine and 5-40μg/mL for telmisartan. The results of analysis have been validated statistically and by recovery studies.