SPECTROPHOTOMETRIC DETERMINATION OF RIFAMPIN IN THE PRESENCE OF ITS DEGRADATION PRODUCTS IN PHARMACEUTICAL PREPARATIONS

The determination of rifampin in the presence of its main degradation products, 3-formyl rifampin and rifampin quinone using two spectrophot ometric methods is described. Both Glenn's method and first derivative spectrophotometry were successfully adopted. No preliminary separatio n steps were required in either cases. Both methods gave accurate and reproducible results for the determination of the drug in dosage forms . The percentage recoveries ranged from 99.33% +/- 0.63 to 100.2% +/- 0.44. The proposed methods are more simple, rapid than other existing methods and can be readily adopted in control laboratory.