Determination of norfloxacin using gold nanoparticles catalyzed cerium(IV)–sodium sulfite chemiluminescence

A rapid flow-injection chemiluminescence (CL) method is proposed for the determination of norfloxacin (NFLX). The method is based on the fact that the weak CL from the redox reaction of Ce(IV)–Na2SO3 can be greatly strengthened by gold nanoparticles (NPs). UV–visible spectra, fluorescence spectra and transmission electron microscopy (TEM) studies are carried out before and after the CL reactions to investigate the CL reinforcing mechanism. The mechanism is supposed to originate from the reinforcer of gold NPs, which facilitates the radical generations and electron-transfer processes taking place on the surface of the gold NPs. Under the selected experimental conditions, a linear relationship was obtained between the CL intensity and the concentrations of NFLX in the range 7.9×10−7 to 1.9×10−5 M and the detection limit was 8.2×10−8 M. This method is successfully applied to the determination of NFLX in human urine.