Flow-injection chemiluminescence determination of fluoroquinolones

A new flow-injection CL method was developed for the determination of fluor oquinolones including ofloxacin, norfloxacin, ciprofloxacin and lomefloxaci n in pharmaceutical preparations, based on the chemiluminescence reaction o f 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 li mits are 0.016 mu g ml(-1) for ofloxacin and 0.16 mu g ml(-1) for norfloxac in, ciprofloxacin and lomefloxacin, respectively. The relative standard dev iations (RSD) are 2.1 to 2.6% (n = 10) for these fluoroquinolones. The anal ytical procedure has been applied to the determination of the fluoroquinolo nes in pharmaceutical commercial formulations. The results are in agreement with those obtained by the official methods.