Dysprosium-sensitized chemiluminescence reactions: Their mechanism and application to the determination of synthetic quinolone antibiotics

Abstract

Dysprosium-sensitized chemiluminescence (CL) reactions have been suggested for the determination of enoxacin (ENX), fleroxacin (FLX), pefloxacin (PFX) and pipemidic acid (PPA). The CL conditions of Dy+3-ENX-MnO4−-S2O3−2-HNO3, Dy+3-FLX-MnO4−-S2O3−2-H6P4O13, Dy+3-PFX-MnO4−-S2O3−2-HCl, and Dy+3-PPA-MnO4−-S2O3−2-H2SO4 systems were investigated and optimized. The CL spectra are formed from the narrow characteristic emission of Dy+3 at 482 and 578 nm through the intermolecular energy transfer from the excited SO2* to analyte, followed by intramolecular energy transfer from analyte* to Dy+3. The calibration curves for the four analytes have good linearity. The relative standard deviations (RSDs) are in the range of 1.6–1.9% for 11 determinations of 6.0 × 10−8 g/mL of ENX, FLX, PFX, and PPA. The detection limits (3σ) are in the range of 2.2 × 10−10–6.0 × 10−10 g/mL. The proposed four CL-based methods have high sensitivity, precision and potential capability for the determination of residues of quinolone synthetic antibiotics in foods and biological samples.