Normal-Phase TLC and Gradient Reversed-Phase HPLC for the Simultaneous Determination of Enrofloxacin and Bromhexine HCl in Presence of Two of Their Official Impurities

Abstract

In this work, two chromatographic methods are developed and validated for determination of enrofloxacin (ENR) and bromhexine HCl (BRM) in the presence of two of their specified impurities, ciprofloxacin (CIP) and BRM impurity C. The suggested chromatographic methods included the use of thin layer chromatography (TLC-densitometry) and high performance liquid chromatography (HPLC). In case of TLC- densitometry, good separation was achieved by using mobile phase of n.butanol: acetone: water: glacial acetic acid: triethylamine (10:3:1:0.5:0.5, by volume) on silica gel stationary phase at 254nm detection. The developed HPLC method used BDS HYPERSIL C18 column with a linear gradient elution of 75-10%, 20-50% and 5-40% for water, acetonitrile and methanol, respectively, in 10 min at a flow rate of 1.5 mL min-1.These methods were sufficient to separate the four substances simultaneously and they are validated as per International Conference on Harmonization (ICH) guidelines.