A.B. Tabrizi


A new, simple, sensitive and rapid spectrofluorimetric method for the determination of piroxicam and propranolol in pharmaceutical formulations has been described. The method is based on the oxidation of piroxicam and propranolol with cerium (IV) to produce cerium (III), whose fluorescence was monitored at 352 nm while excited at 255 nm. The variables affecting oxidation of these drugs were studied and optimized. Under the experimental conditions, the calibration graphs were linear over the range of 0.02-3.0 and 0.02-2.4 mg/L, respectively, for piroxicam and propranolol. The limit of detection for piroxicam and propranolol was 0.006 and 0.008 mg/L, respectively, and the relative standard deviation of 5 replicate determinations of these drugs at 1.0 mg/L concentration level was 1.65 and 1.79%, respectively. Good recoveries in the range of 95-108% were obtained for spiked samples. The proposed methods were successfully applied to the determination of piroxicam and propranolol in commercial pharmaceutical formulations.