Application of Lanthanide-Sensitised Chemiluminescence to the Determination of Levofloxacin, Moxifloxacin and Trovafloxacin in Tablets

摘要

A flow injection method including chemiluminescence detection has been developed and applied to the determination of fluoroquinolones levofloxacin, moxifloxacin and trovafloxacin in tablets. The proposed method is based on the luminescent properties of the system Ce(IV)–sulphite–fluoroquinolone and the addition of a trivalent lanthanide ion as emission-sensitizer. The optimum conditions for chemiluminescence emission were investigated for each fluoroquinolone. The best results were achieved when employing Eu(III) as lanthanide cation for levofloxacin and moxifloxacin, and Tb(III) for trovafloxacin. These fluoroquinolones were determined over the concentration range of 0.5–3.5 µg mL−1, 0.2–3.0 µg mL−1 and 0.008–0.400 µg mL−1, with detection limits of 0.100, 0.035 and 0.008 µg mL−1, respectively. The relative standard deviations were in the range of 1.0–2.5% for all three cases. The method was applied to the determination of three fluoroquinolones in their respective pharmaceutical preparations and compared with an independent UV-spectrophotometric method. The results were satisfactory.