The development of the hot electron-induced cathodic electrochemiluminescence (HECL) often accompanied with the advance in the electrode materials and instruments. In this work, dimethyl silicone oil was employed as the coating layer for initiating the HECL. The insulating layer was obtained by simple drop casting and subsequent polishing, which could withstand high voltage and meet the requirement of HECL. With the asprepared interface, the quantitative detection of puerarin in the aqueous solution was achieved based on the quenching effect on the SO 4 *À .