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利用种子生长法合成Au@Ag核壳材料,并用透射电镜、紫外可见光谱对其进行表征,以其作为分子信标构建电化学适配体传感器,用以分析检测水体中的Hg2+.通过T-Hg2+-T化学结合作用,在电极表面聚集多个Au@Ag单元进行信号放大,实现对Hg2的高灵敏检测.在最优实验条件下,示差脉冲伏安法(DPV)实验结果表明,电流响应随Hg2+浓度的增加而增加,并在0.5 ～ 50 nmol/L的范围内呈现良好线性相关性,该传感器对Hg2+的检出限低至0.03 nmol/L.将此方法应用于检测实际水体中的Hg2+,其加标回收率为91.6％ ～ 110.3％.“,”Au@Ag core-shell nanostructure owns higher catalytic activity than alloy or monometal nanoparticles due to synergistic effect between Au and Ag.In this study,Au@Ag core-shell nanomaterials were synthesized by seed-mediated growth method,which were characterized by transmission electron microscope (TEM) and UV-Vis spectrometry (UV-vis).The novel electrochemical aptasensor was constructed by using Au@Ag core-shell nanomaterial as label for detection of Hg2+ in water sample.Meanwhile,the electrochemical signal was amplified by aggregating Au@Ag labels on the surface of electrode based on T-Hg2+-T,which achieved a sensitive detection of Hg2+.Under optimal conditions,the sensor presented good electrochemical responses to Hg2+ concentration.The result of pulse voltammetry (DPV) showed the current responses increased with the increasing of Hg2+concentration,which exhibited linear in the range of 0.5 ～ 50 nmol/L with a detection limit of 0.03 nmol/L.More importantly,this developed biosensor could be applied in detecting Hg2+ in real water sample,and the recoveries of standard addition in water varied from 91.6 ％ ～ 110.3 ％.