Flow-injection chemiluminescence determination of fluoroquinolones

A new flow-injection CL method was developed for the determination of fluoroquinolones including ofloxacin, norfloxacin, ciprofloxacin and lomefloxacin in pharmaceutical preparations, based on the chemiluminescence reaction of sulphite with cerium(IV) sensitized by these compounds. The linear ranges are 0.04 to 4.0 mu g ml(-1) for ofloxacin and 0.4 to 40.0 mu g ml(-1) for norfloxacin, ciprofloxacin and lomefloxacin, respectively. The detection limits are 0.016 mu g ml(-1) for ofloxacin and 0.16 mu g ml(-1) for norfloxacin, ciprofloxacin and lomefloxacin, respectively. The relative standard deviations (RSD) are 2.1 to 2.6% (n = 10) for these fluoroquinolones. The analytical procedure has been applied to the determination of the fluoroquinolones in pharmaceutical commercial formulations. The results are in agreement with those obtained by the official methods.