Carbon nanotubes/Au nanoparticles ( CNT/AuNP ) composite film was fabricated on glassy carbon electrode ( GCE) by first dropping CNTs on the electrode surface and then electrodeposition of AuNPs by multi-potential step. The antibody of microcystin-( leucine-arginine ) ( anti-MCLR ) was immobilized on the modified electrode surface through adsorption on AuNPs. Subsequently, bovine serum albumin ( BSA) was used to block the non-specific adsorption to obtain the immunosensor for MCLR assay. The immunosensor could effectively capture MCLR by the specific immunoreaction between the electrode surface-confined antibody and MCLR, followed by the attachment of the anti-MCLR HRP-labeled to form a sandwich-type system. The analysis of MCLR was performed based on the catalytic reaction of HRP toward the oxidation of hydroquinone ( QH2 ) by H2 O2 . Under the optimal experimental conditions, the peak current response increased linearly with the concentration of MCLR in the range of 0 . 50-12 μg/L with a detection limit of 0. 30 μg/L (S/N=3). The developed immunosensor was used to determine MCLR in real water samples, and the recoveries of standard addition experiments were in the range of 93 . 0%-108 . 5%, with the relative standard deviation of 3 . 8%-5 . 0%.%在玻碳电极表面修饰碳纳米管，并用多电位阶跃法在碳纳米管表面沉积纳米金制得碳纳米管/纳米金复合膜。通过纳米金和微囊藻毒素-(亮氨酸-精氨酸)抗体之间的吸附作用，将抗微囊藻单克隆抗体固定于电极表面，以牛血清白蛋白封闭非特异性吸附位点，研制了检测微囊藻毒素的电化学免疫传感器。利用微囊藻毒素与其抗体之间的特异性识别作用构建“三明治”夹心结构的免疫分析模式，以辣根过氧化物酶标记抗体为二抗，利用微分脉冲伏安法实现了对微囊藻毒素的检测。在优化条件下，此传感器的响应电流与微囊藻毒素浓度在0.50~12.0μg/L范围内呈良好的线性关系，检出限为0.30μg/L(S/N=3)。对实际水样进行了微囊藻毒素的加标回收实验，回收率在93.0%~108.5%之间，相对标准偏差为3.8%~5.0%。
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