摘要

In the present study, we report on a simple, sensitive and selective chemosensor for the recognition and monitoring of silver ions in aqueous solutions. It is based on the inhibitory effect of Ag(I) ion on the chemiluminescence signal of H2O2-luminol system, which could be improved by at least 10-folds in the presence of cobalt ferrite (CoFe2O4) magnetic nano-particles. The structure and morphology of the synthesized CoFe2O4 nano-particles were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. The as-prepared CoFe2O4 nano-particles were then used as catalysts for H2O2-luminol chemiluminescence system. The enhanced chemiluminescence signal was dramatically decreased by adding trace levels of Ag(I) ion into the solution. The possible mechanism to explain this finding was discussed. Several parameters affecting the analytical signal such as the pH value, the concentrations of H2O2, luminal and CoFe2O4 nano-particles, incubation time and interfering ions were investigated and optimized. Under the optimized experimental conditions, chemiluminescence intensity of luminol-H2O2-CoFe2O4 versus Ag(I) concentration gave a linear response within the range of 0.5-100 ng mL(-1) with a detection limit of 0.15 ng mL(-1). The method was successfully applied to monitoring Ag(I) in various water samples.

  • 出版日期2015-3-31