Utilization of Acid Dyes for Spectrophotometric Determination of Moxifloxacin and Enrofloxacin Hydrochlorides in Dosage Forms

Simple, rapid and extractive spectrophotometric methods were developed for the determination of some fluoroquinolone antibiotics: moxifloxacin hydrochloride (MXF), and enrofloxacin (ENF) in pure forms and pharmaceutical formulations.These methods are based on the formation of ion-pair complexes between the basic drugs and acid dyes, namely, methylene blue (MB) and methyl orange (MO) in acidic buffer solutions.The formed complexes were extracted with chloroform and measured at 416, and 422 nm for MB and MO respectively, for MXF; at 415 and 420 nm for MB and MO respectively, for ENF.The analytical parameters and their effects are investigated.Beer's law was obeyed in the ranges 2.0-20, 4.0-24, and 3.0-30 and 3.0-18 µg/ml for the drug MXF and ENF using MB and MO, respectively.The proposed methods have been applied successfully for the analysis of the studied drugs in pure forms and pharmaceutical formulations.Statistical comparison of the results with the reference methods showed excellent agreement and indicated no significant difference in accuracy and precision.