Spectrophotometric Determination of Chloramphenicol in Pharmaceutical Preparations

Abstract

Two simple, rapid and sensitive spectrophotometric methods have been developed for
the determination of chloramphenicol (CAP) in pure form and in pharmaceutical preparations.
The proposed methods are based on a coupling reaction between reduced chloramphenicol
(by zinc powder and concentrated hydrochloric acid) with chromatropic acid or phenol in the
presence of ammonium hydroxide to form an intense red violet or yellow color, watersoluble
dyes that are stable and have a maximum absorption at 515 nm using chromatropic
acid and 432 nm on using phenol. The calibration graphs were linear over the concentration
ranges of 0.52 -12 μg mL-1 and 0.4- 18μg mL-1 with a limit of detection (LOD) of 0.1334 μg
mL-1 and 0.0873 μg mL-1 for chromatropic acid and phenol, respectively. The proposed
methods were successfully applied to the determination of CAP in ointment and eye drops.