Development of Classical Least Square Method for the Determination of Candesartan and Hydrochlorthiazide in Tablet Dosage Form

A new simple spectrophotometric method was developed for the determination of binary mixtures of Candesartan cilexetil (CAND) and Hydrochalorothiazide (HCTZ), without prior separation. The method is based on the multi-wavelength technique i.e. classical least square (CLS) method. The tablet is determined by the multi-wavelength technique (CLS), at the wavelengths range of 215-225 nm over the concentration ranges of 2.5-50 and 1-30 μg/mL with mean recovery more than 98% for both drugs CAND and HCTZ, respectively. The proposed spectrophotometric method was validated and successfully applied for the assay of drug combination in several laboratory-prepared mixtures and commercial tablets.