采用自组装方法将L-半胱氨酸、戊二醛、Anti-IgG和h-IgG依次固定在裸金电极表面,制备了无标记阻抗型免疫球蛋白G(h-IgG)生物免疫传感器,并以巯基席夫碱镍配合物修饰的纳米金作为电化学检测探针。采用交流阻抗法对电极性能进行了表征,并用于h-IgG含量的测定。结果表明:h-IgG的质量浓度在10~100 μg·L-1范围内与阻抗值呈线性关系,检出限(3s/k)为4.54×10-7g·L-1。该生物传感器用于h-IgG溶液的测定,平行测定10次,相对标准偏差(n=10)为0.55%。

Unmarked Impedance Type immunoglobulin G (h-IgG) immuno bio-sensor was prepared by self-assembly of L-cysteine, glutaraldehyde, Anti-IgG and h-IgG on the surface of bare gold electrode, and Au nanoparticles modified with complex of Ni(Ⅱ) and thiol-schiff base was prepared and used as electrochemical probe. The surface of the electrode was characterized and the content of h-IgG was determined by AC impedance method. Linear relationship between value of impedance and mass concentration of h-IgG was kept in the range of 10-100 μg·L-1, with detection limit (3s/k) of 4.54×10-7g·L-1. Value of RSD (n=10) found with a same modified electrode in 10 successive determinations of h-IgG solution was 0.55%.