New spectrophotometric determination of roxithromycin in pharmaceutical preparations and environmental samples

Abstract

A new, simple, selective, sensitive and accurate direct spectrophotometric method has
been developed for the determination of roxithromycin in pure form , pharmaceutical
preparations and environmental water samples. The method was based on the reaction of
roxithromycin with concentrated sulfuric acid to form red color product having
absorption maxima at 485nm .The molar absorptivity of the proposed method was
1.34×105 l. mol-1. cm -1 and its absorbance was linear with concentration rang 5- 50
μg/ml . The relative standard deviation of the method was less than 2% and accuracy
(average recovery ) was 99.98% .The substance commonly found with roxithromycin
did not interfere .The advantages of the proposed method include a high sensitivity and
considered to be simple because it does not need heating or solvent extraction steps .
The proposed method was successfully applied to the determination of roxithromycin in
pure form ,pharmaceutical preparations and in environmental water samples.