Abstract
A fully validated and simple spectrofluorimetric method was developed for the determination of azithromycin, clarithromycin, erythromycin ethylsuccinate, erythromycin stearate and roxithromycin in bulk powders and their dosage forms. The proposed method was based on ion pair formation of either one of the cited drugs with eosin-G dye in presence of Mcllvaine buffer and the resultant complex was extracted by chloroform. All variables affecting the intensity of the developed fluorescence products were studied and optimized. Straight line correlation was found over concentration ranges of 0.04-0.2, 0.4-6.4, 4.0-16, 1.6-12, 0.4-4.0 mu g ml(-1) azithromycin, clarithromycin, erythromycin ethylsuccinate, erythromycin stearate and roxithromycin respectively, with god correlation coefficients (0.9973 - 0.9994). The limits of detection and quantitation for this method ranged from 0.01 to 1.74 mu g ml(-1) and from 0.04 to 5.79 mu g ml(-1) respectively. The relative standard deviations were 1.54-2.15%. The proposed method was applied successfully for the determination of the cited drugs in different pharmaceutical dosage forms as tablets, capsules, granules as well as suspension without interference from common encountered additives with overall percentage recoveries ranged from 94.74 +/- 1.17 to 100.20 +/- 1.57. In addition no interference was observed due to other active ingredients as trimethoprim and sulfisoxazole acetyl. The results were compared favorably with those of reported method.