金纳米颗粒碳电极固载布鲁氏菌抗体免疫传感器的研究

Study on antibody immobilization biosensor of Brucella with gold nanoparticles-modified carbon electrode

提出并建立一种金纳米颗粒修饰碳电极固载布鲁氏菌抗体免疫传感器,用于布鲁氏菌的快速检测。采用丝网印刷金纳米颗粒碳电极作为工作电极,利用金纳米颗粒表面积大的特点,在工作电极表面修饰布鲁氏菌抗体,构建电化学三电极体系。通过循环伏安法(CV法)表征免疫电极的电化学反应过程。以氧化峰电流的变化值(ΔI_(pa))作为电流响应信号,PBS缓冲液为空白对照,结果表明布鲁氏菌抗原与抗体免疫结合导致氧化峰电流减小,而无菌的PBS缓冲液电流值则几乎没有变化,用大肠杆菌、金黄色葡萄球菌代替布鲁氏菌进行检测,干扰菌的响应信号与空白液相当,因此免疫传感器对布鲁氏菌有较好的特异性。

An immunosensor fabricated by immobilizing Brucella antibody onto the surface of gold nanoparticles-modified screen-printed carbon electrodes(GNPs-SPCEs)was proposed for the rapid detection of Brucella.The gold nanoparticle carbon electrode was used as the working electrode,and the Brucella antibody was modified on the surface of the working electrode to construct the electrochemical three electrode system.The reaction process was characterized by cyclic voltammetry(CV).The change value of oxidation peak current(ΔIPA)was used as the current response signal,and PBS buffer was used as blank control.It was found that when the antigen of Brucella combined with antibody,the oxidation peak current decreased,while the current value of sterile PBS buffer almost did not change.When Escherichia coli and Staphylococcus aureus were used to replace Brucella,the response signal of interfering bacteria was similar to that of blank solution.Therefore,the immunosensor has good specificity for Brucella.