Spectrophotometric determination of ofloxacin and lomefloxacin hydrochloride with some sulphonphthalein dyes

Three spectrophotometric methods for the determination of ofloxacin and lomefloxacin hydrochloride are proposed which are based on their extraction into chloroform as ion pairs with Bromophenol Blue (BPB), Bromothymol Blue (BTB) and Bromocresol Purple (BCP). The calibration graphs generated were linear over the range 5-25, 2-15 and 2-20 mu g ml(-1) of drug in chloroform, using three dyes, respectively. The composition of the ion pair was established by continuous variation and molar ratio methods. The described methods were utilized for assaying ofloxacin and lomefloxacin hydrochloride in pharmaceutical preparations.