Electrochemiluminescence sensor based on EuS nanocrystals for ultrasensitive detection of mercury ions in seafood

In this work, the electrochemiluminescence (ECL) of europium sulfide nanocrystals (EuS NCs) in K 2 S 2 O 8 cathode co-reagents was studied. Based on selective quenching of the ECL emission from EuS NCs by Hg 2+ , a novel label-free ECL sensor for the highly sensitive and selective detection of Hg 2+ was developed. A linear response between the ECL intensity and the concentration of Hg 2+ was obtained in the range from 0.1 pM to 10 5 pM, achieving a detection limit of 0.028 pM. Moreover, this sensor was also successfully applied to the detection of Hg 2+ in seafood with good recovery. The current study provides a green and feasible method for the detection of trace Hg 2+ in seafood. • The electrochemiluminescence (ECL) of EuS nanocrystals was reported. • An intensive and stable cathode ECL emission at − 2.0 V was observed. • The ECL sensor with high selectivity and stability was achieved for detecting Hg 2+ . • This sensor was successfully applied for Hg 2+ detection in seafood.