Table of Contents Author Guidelines Submit a Manuscript
Journal of Spectroscopy
Volume 2013, Article ID 214270, 13 pages
Research Article

New Spectrophotometric and Conductometric Methods for Macrolide Antibiotics Determination in Pure and Pharmaceutical Dosage Forms Using Rose Bengal

Department of Analytical Chemistry, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt

Received 20 June 2012; Revised 30 November 2012; Accepted 30 November 2012

Academic Editor: María Carmen Yebra-Biurrun

Copyright © 2013 Rania A. Sayed et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Two Simple, accurate, precise, and rapid spectrophotometric and conductometric methods were developed for the estimation of erythromycin thiocyanate (I), clarithromycin (II), and azithromycin dihydrate (III) in both pure and pharmaceutical dosage forms. The spectrophotometric procedure depends on the reaction of rose bengal and copper with the cited drugs to form stable ternary complexes which are extractable with methylene chloride, and the absorbances were measured at 558, 557, and 560 nm for (I), (II), and (III), respectively. The conductometric method depends on the formation of an ion-pair complex between the studied drug and rose bengal. For the spectrophotometric method, Beer's law was obeyed. The correlation coefficient ( ) for the studied drugs was found to be 0.9999. The molar absorptivity ( ), Sandell’s sensitivity, limit of detection (LOD), and limit of quantification (LOQ) were also calculated. The proposed methods were successfully applied for the determination of certain pharmaceutical dosage forms containing the studied drugs