Kinetic Spectrophotometric Methods for the Determination of Chloramphenicol in Pharmaceutical Preparations

Simple and sensitive kinetic methods are described for the determination of chloramphenicol in pure form and pharmaceutical preparations. The methods are based on oxidative – coupling reaction between reduced chloramphenicol (by zinc powder and concentrated hydrochloric acid) with promethazine hydrochloride in the presence of sodium periodate yielding a highly colored product at room temperature, the reaction is followed spectrophotometriclly at λmax= 590 nm. Initial rate and fixed time (at 20 minutes) methods are utilized for concentration determination. The calibration graphs were linear in the concentration ranges (2-20 μg.ml-1) and (0.5-30 μg.ml-1) respectively. The results were validated statistically and checked through recovery studies, and have been applied successfully for the determination of chloramphenicol in commercial dosage forms.