基于Nafion-石墨烯复合物固定甲胎蛋白电化学免疫传感器的研究

An electrochemical immunosensor for alpha fetoprotein based on graphene-nafion nanocomposite

该文利用Nation-石墨烯复合物和纳米金固定甲胎蛋白抗体（anti—AFP）。构建了高灵敏的电化学免疫传感器。首先将石墨烯分散在Nation溶液中制得Nation一石墨烯的复合膜，并将其固定在玻碳电极（GCE）表面，通过静电吸附和共价键合作用将硫堇（Thi）和纳米金颗粒（nano—Au）依次固定到Nation-石墨烯复合膜修饰的玻碳电极表面。再通过纳米金单层吸附anti—AFP，最后用牛血清蛋白（BSA）封闭电极上的非特异性吸附位点，从而制得了甲胎蛋白免疫传感器。实验结果表明，该修饰电极对不同浓度的甲胎蛋白（AFP）有很好的响应，其线性范围为0．8～100ng／mL，检出限为O．36ng／mL。

A highly sensitive electrochemical immunosensor for the determination of Alpha Fetoprotein （AFP） was developed based on the muhilayer, comprised of Nafion, grapheme and thionine （Thi）. First, the graphene composite was prepared by dispersing grapheme in Nafion solution, and dropped onto the surface of glass carbon electrode to form a stable film. Secondly, the obtained electrode was immersed in Thi solution to absorb the Thi molecules. And then, the nano-Au monofilm was formed by the interaction between the amino groups of Thi and Au. Finally, the prepared electrode was fabricated by anti-AFP and block by BSA. The stepwise fabrication process of the immunosensor was characterized by the cyclic vohammetrys, and experimental results show that the immunosensor have good current response on AFP from 0.8 - 100 ng/mL with a detection limit of 0.36 ng/mL.