Aggregation-induced chemiluminescence system for sensitive detection of mercury ions.

As mercury ions (Hg2+) are emanated to surroundings in the course of various natural events and human activities, an accurate sensing of Hg2+ is essential for human health and environmental protection. Herein, a new aggregation-induced chemiluminescence (CL) sensor for fast, sensitive, and selective detection of Hg2+ is developed, based on the CL enhancement of bis(2,4,6-trichlorophenyl)oxalate (TCPO)-H2O2 system by thiolate-protected gold complexes (Au(I)-thiolate complexes) in the aggregated state. Because Hg2+ has a strong interaction with hydrosulfuryl (-SH) groups in Au(I)-thiolate complexes, the aggregation is disrupted and the CL is quenched. The decrease of CL intensity is proportional to Hg2+ contents with a linear range of 0.005-10 μg mL-1 and the limit of detection (LOD) is 3 ng mL-1. To the best of our knowledge, this is the first AIE CL sensor for Hg2+ detection. The study opens up attractive perspectives for developing simple and rapid aggregation-induced CL methods in monitoring heavy metals.