采用纳米金作为抗体的固定基质,同时以硫堇为电活性指示剂,构建了一种免标记的电化学免疫传感器用于微囊藻毒素-LR(MC-LR)的灵敏检测。将萘酚修饰到金电极表面,通过静电作用将硫堇捕获。加入纳米金与硫堇的氨基结合,抗体将通过与纳米金作用而固定到电极表面。通过MC-LR与其相应抗体的特异性结合作用阻碍硫堇的电子传递,实现MC-LR的电化学检测。在最优实验条件下,MC-LR的质量浓度与电信号在5~100μg/L范围内呈良好的线性关系,检出限为0.71μg/L,可满足饮用水检测需求,能够用于实际水样中M C-LR的测定。 Nanometer gold was used as the immobilization matrix of the antibody, and a thionine-free electroactive indicator was used to construct a label-free electrochemical immunosensor for the sensitive detection of microcystin-LR (MC-LR). Naphthol was modified to the surface of gold electrode to capture thionine by electrostatic interaction. Nano gold is added to combine with the amino group of thionine, and the antibody is immobilized to the electrode surface by the action of gold nanoparticles. Through the specific binding of MC-LR and its corresponding antibody, it blocked the electron transfer of thionine and achieved the electrochemical detection of MC-LR. Under the optimal experimental conditions, the mass concentration of MC-LR showed a good linear relationship with the electrical signal in the range of 5 ~ 100μg / L, the detection limit was 0.71μg / L, which could meet the needs of drinking water testing and could be used in practical Determination of M C-LR in water samples.