Quantitative detection of several heavy metals by modified surface enhanced Raman substrate

Abstract:

Heavy metal ions have a serious impact on water quality and its application, and the development of a highly selective and sensitive detection platform for heavy metal ions has great significance in the water resources protection. The surface-enhanced Raman (SERS) sol substrate was prepared by using 4-MBA to modified gold nanoparticles as a carrier, which has strong selectivity and high sensitivity to heavy metal ions such as Pb2+, Cd2+, and As3+ in aqueous solution. The experiments found that the Raman detection spectra of Pb2+, Cd2+ and As3+ by the SERS substrate have obvious shifts in vibration frequency bands and peak intensities near 1046cm-1, 1075cm-1, and 1587cm-1. An optimized enhanced substrate was obtained by optimizing the sol-substrate, which can distinguish three kinds of heavy metal ions. The detection limit for heavy metal ions can reach 0.1mg/L, and it has a linear relationship in the range of 0.5 to 100 mg/L. A standard addition verification experiment was performed on Pb2+ in real water samples. This substrate provides a fast and convenient method for heavy metal identification and detection with better enhancement effect and heavy metal quantitative analysis ability, and provides an effective means for the efficient detection of heavy metal ions in water.