Simple, sensitive, accurate and precise spectrophotometric methods for quantitative determination of five drugs viz., Tramadol Hydrochloride (TDH), Dobutamine (DOB), Trimetazidine (TRMZ), Terazocin (TRZ) and Esmolol (ESM) were developed. The method for each drug depends upon oxidation of drugs by Ce (IV) (Excess) and estimating the amount of un reacted Ce (IV) by Rhodamine-B dye at 557 nm. The calibration curves obeyed Beer's law over the concentration range of 14-130 mu g ml(-1) (TDH), 1-14 mu g ml(-1) (DOB), 8-120 mu g ml(-1) (TRMZ), 16-130 mu g ml(-1) (TRZ), and 12-84 mu g ml-1 (ESM). The methods have been validated in terms of guidelines of ICH and has been applied to the analysis of pharmaceuticals.
