FI-Fluorophotometric Determination of Enoxacin

In a hexamine-HCl buffer solution of pH 5.80, synergistic sensitization effect of sodium dodecyl sulfate (SDS) and Al(Ⅲ) on the fluorescence of enoxacin was observed. Based on this fact, and by applying the flow injection technique with time scanning mode, a new fluorophotometric method for the determination of enoxacin was proposed. Linear relationship was found between values of fluorescence intensity measured at wavelengths of 267.0 nm (λex) and 400.0 nm (λem) and mass concentration of enoxacin in the range of 0.002-0.8 mg·L-1. Values of detection limit (3S/N) was 1.7 μg·L-1. The proposed method was used in the determination of enoxacin in the samples of tablets, capsules and injections, giving values of average recovery of 98.5%, 100.5% and 98.0%, and average RSD (n=5) of 2.1%, 1.3% and 1.6% respectively.