Objective: The objective of the study was to develop and validate a new rapid and more sensitive Reverse Phase High-Performance Liquid Chromatography (RP-HPLC) method for the simultaneous estimation of azithromycin, fluconazole and ornidazole in bulk and pharmaceutical dosage forms.

Methods: Separation was achieved with a cap cell pack C18 column (4.6 x 250 mm, 5μ) with an isocratic mobile phase containing a mixture of acetonitrile and phosphate buffer pH 4.8 [adjusted with ortho-phosphoric acid] (50:50 % v/v) at the flow rate of 1 ml/min and detection was monitored at 210 nm.

Results: The retention time (Rt) of azithromycin, fluconazole and ornidazole were found to be 4.82±0.01, 5.25±0.01 and 6.33±0.01 min respectively. The precision was found with<1.5% of %RSD. The calibration curve was linear over the concentration ranging from 500-1000 µg/ml for azithromycin, 75-150 µg/ml for fluconazole and 375-750 µg/ml for ornidazole with the correlation coefficient (r2) of 0.999. The percentage recovery was found to be within the specified range i.e., 98-102 % for three drugs. Limit of detection (LOD) was found to be 5.810, 1.790 and 4.924 µg/ml, whereas Limit of quantification limits (LOQ) was found to be 9.834, 2.667 and 7.980 µg/ml, respectively.

Conclusion: A simple isocratic liquid chromatographic method was developed and validated for simultaneous estimation of azithromycin, fluconazole and ornidazole in their formulations. Due to its simplicity, rapidness and specificity, it can be applied for routine quality control analysis of these drugs.
Keywords: Azithromycin, Fluconazole, Ornidazole, Method development, RP-HPLC