Spectrofluorimetric method for determination of some angiotensin Ⅱ receptor antagonists

A simple,rapid,accurate and highly sensitive spectrofluorimetric method has been developed for determination of some angiotensin Ⅱ receptor antagonists (AIIRA's),namely Losartan potassium (Los-K),Irbesartan (Irb),Valsartan (Val) and Candesartan cilexetil (Cand) in pure forms as well as in their pharmaceutical dosage forms.All the variables affecting the relative fluorescence intensity (RFI) were studied and optimized.Under the optimum conditions,linear relationships with good correlation coefficients (0.9982-0.9991) were obtained over the concentra tion range from 0.006μg/mL to 1.7μg/mL.Good accuracy and precision were successfully obtained for the analysis of tablets containing each drug alone or combined with hydrochlor othiazide (HCTZ) without interferences from the co-formulated HCTZ or the additives commonly present in tablets.