聚苯乙烯和聚乙烯醇作粘结剂的新型碳糊电极用于构建电化学免疫传感器的研究

Study on Electrochemical Immunosensor Construction Based on New Carbon Paste Electrode Using Polyvinyl Alcohol-Doped Polystyrene as Adhesive

利用掺杂聚乙烯醇的聚苯乙烯作粘结剂,制备成新型碳糊电极,该电极具有制作简单、导电性能良好和改进的表面吸附性能,可用于构建基于表面吸附固定生物组分的电化学免疫传感器。用转铁蛋白-转铁蛋白抗体作模式分析物,辣根过氧化物酶(HRP)作为酶标,建议的免疫传感器测定人转铁蛋白的线性关系是0.50～70.0μg/mL(相关系数为0.983),免疫传感器在使用后可通过简单的打磨抛光更新,表现出良好的重复使用性。

A new strategy to constructing amperometric immunosensor for transferrin assay based on improved carbon paste electrode （CPE） as sensing platform has been described. The CPE is prepared by employing polyvinyl alcohol-doped polystyrene as the novel adhesive. The obtained CPE has good conductivity and better surface -adsorption capability. A sequential competitive immunoassay format was performed on the surface of CPE by using transferrin and transferrin antibody as a model system. The assay comprised first loading of the transferrin antibody on surface of CPE, then blocked in BSA solution followed by a competitive incubation in the buffer containing the transferrin （analyte） and transferrin labeled with horseradish peroxidase （SjAg-HRP） and finally the amperometric detection. The feasibility of regenerating surface of CPE for consecutive assays is demonstrated by a simple polish after each determination. The dynamic concentration range for transferrin assay is 0.50 - 70.0 μ g/mL.