Using Gold Nanoparticles with Spectroscopic and Analytical Models for Rapid Colorimetric Detection of Mercury Ions in Aqueous Media

Abstract

In this study, high-sensitively colorimetric detection of mercury ions was developed according to the surface plasmon resonance of modified gold nanoparticles. While in a citrate buffer solution, the selected modifier Bismuthiol II can cause gold nanoparticles to aggregate. Gold nanoparticles with a spherical shape and average diameter of about 13 nm were prepared. While mercury ions can inhibit gold nanoparticle aggregation, after the addition of mercury ions, the color of the gold nanoparticles solution changes from light violet to red with a hypochromatic shift at the absorption peak. By collecting the UV-Vis spectrum of the solution after the reaction, the characteristic bands are selected to build a partial least squares model. Both the 0.9477 correlation coefficient with a 0.0986 mg/L standard deviation for the calibration set, and 0.9274 correlation coefficient with a 0.1020 mg/L standard deviation for the prediction set were obtained via a partial least squares model.