▎ 摘　　要

In order to satisfy the needs for the trace microcystins in water, a novel electrochemiluminescence (ECL) immunosensor was developed based on a dual signal amplification strategy. A MoS2-Au hybrid nanocomposite served as the matrix to add a large number of active-sites, and graphene nanosheets were employed as the scaffold to capture cadmium-selenide quantum dots (CdSe QDs). Transmission electron microscopy (TEM), scanning electron microscopy (SEM), ultraviolet-visible absorption spectroscopy and photoluminescence spectroscopy were used to characterize these materials. The fabrication of the immunosensor was performed by electrochemical impedance spectroscopy (EIS). Under the optimum conditions, a strong ECL signal was obtained from immunosensor that was approximately 7-fold higher than from an immunosensor with a pure CdSe QDs probe. The ECL immunosensor possesses a wide linear response to microcystins-LR (MCLR) from 0.005 to 100 mu g/L with a low detection limit of 0.0032 mu g/L. Moreover, the immunosensor exhibited good selectivity, stability, and reproducibility for MCLR.