Abstract

NEW SPECTROPHOTOMETRIC DETERMINATION OF AZITHROMYCIN IN PURE AND DOSAGE FORMS USING NBROMOSUCCINIMIDE AND POTASSIUM PERMANGANATE AS OXIDANTS

Hany A. Omara*, Hawa A. Ahmed, Abeer A. El-Mahdy and Salha A. Musbah

ABSTRACT

Two simple, rapid, accurate, sensitive and economical visible spectrophotometric (indirect) methods (A and B) for the determination of azithromycin (AZT) in bulk sample and in dosage forms are described. The first method is based on the oxidation of the drug by Nbromosuccinimide (NBS) and determination of the unreacted NBS by measurement of the decrease in absorbance of methyl orange dye (MO) at a suitable λmax = 507 nm. The absorbance concentration plot is linear over the range (0.2-4.5 μg/ml). The second method is based on oxidation of AZT by potassium permanganate in acidic medium, and determination of the unreacted oxidant by measuring the decrease in absorbance using three different dyes; methylene blue (MB), orange G (OG) and malachite green dye (MG) at a suitable λmax (660, 475 and 617 nm), respectively. Regression analysis of Beer's law plots showed good correlation in the concentration ranges (0.4-38, 0.8-22 and 0.6-16 μg/ml), respectively. The quality control/assurance parameters such as limits of detection (LOD), quantification (LOQ), molar absorptivity and Sandelle’s sensitivity values are also reported. The accuracy and precision of the methods were studied on intra-day and inter-day basis. No interference was observed from common pharmaceutical additives. The methods are used successfully to assay AZT in its pharmaceutical dosage forms viz. tablets and capsules.

Keywords: Azithromycin; Spectrophotometric; Redox reaction; N-bromosuccinimide; Potassium permanganate; Pharmaceutical analysis.