Determination of quinolones residues in prawn using high-performance liquid chromatography with Ce(IV)-Ru(bpy)32+-HNO3 chemiluminescence detection

A novel method was developed for the determination of quinolone (QN) residues such as ofloxacin, norfloxacin, ciprofloxacin and lomefloxacin by high-performance liquid chromatography (HPLC) coupled with chemiluminescence (CL) detection. The procedure was based on the chemiluminescent enhancement by QNs of the Ce(SO4)(2)-Ru(bpy)(3)(2+)-HNO3 system. The separation was carried out with an isocratic elution using the mobile phase of 3:15:82 (v/v/v) acetonitrile-methanol-ammonium acetate buffer (containing 7.5 x 10(-4) M TBAB, 0.8% (v/v) TEA and 1.0 x 10(-4) M ammonium acetate, pH 3.65) at a flow rate of 1.0 ml/min. For the four QNs, the detection limits at a signal-to-noise of 3 ranged from 0.36 to 2.4 ng/ml. The relative standard deviations for the determination of QNs ranged from 1.6 to 4.5% within a day (n = 11) and from 3.7 to 6.2% in three days (n = 15), respectively. The method was successfully applied to the determination of QNs in prawn samples. The possible mechanism of the CL reaction was also discussed briefly. (c) 2006 Elsevier B.V. All rights reserved.