“Turn-On” Chemiluminescence Sensor for the Highly Selective and Ultrasensitive Detection of Hg²⁺ Ions Based on Interstrand Cooperative Coordination and Catalytic Formation of Gold Nanoparticles

Abstract

Monitoring the levels of potentially toxic metal ions such as Hg(2+) in aquatic ecosystems is important because this ion can have severe effects on human health and the environment. Thus, a novel chemiluminescence (CL) sensor is developed for the highly selective and ultrasensitive detection of Hg(2+) ions in aqueous solution, based on thymine-Hg(2+)-thymine (T-Hg(2+)-T) coordination chemistry and subsequent formation of gold nanoparticles (Au NPs) in a HAuCl(4)/NH(2)OH reaction. The thus-formed Au NPs trigger the reaction between luminol and AgNO(3), producing CL emission. This novel CL technique has several advantages including high sensitivity (0.01 ppb) and selectivity over a spectrum of interfering metal ions. In view of these advantages, as well as the cost-effective, minimized working steps and portable features of the CL techniques, we expect that this CL sensor will be a promising candidate for the field detection of toxic Hg(2+) ions in environment, water, and food samples.