微型IgG免疫传感器的制备及其对人免疫球蛋白G的响应

Preparation of a Micro Immunoglobulin G Immunosensor and Its Highly Sensitive Potentiometric Response to Human Immunoglobulin G

以硅烷醇-戊二醛交联法在Ag电极表面制备的抗IgG膜电极为敏感器件,配以Ag/AgCl参比电极制备成微IgG免疫传感器.传感器基于免疫反应的原理,通过其电动势的变化对IgG的Nernst响应,测定人免疫球蛋白(hIgG)的含量.采用两种抗IgG膜电极的传感器,对hIgG的响应时间均小于6 min;线性范围在0.20～2.0 μg/L,检出限为0.1 μg/L.直接检测健康人血清中hIgG 的相对标准偏差为6.2% (n=5);加标回收率为93%～108%.以0.012 mol/L盐酸为再生液,传感器可重复使用,对IgG的活性在4℃可保持30 d.

A micro immunoglobulin G（IgG） immunosensor has been prepared by means of covalent immobilization of anti-IgG on a silver electrode and its highly sensitive Nernst response to human immunoglobulin G （hlgG） has been investigated. This potentiometric response is based on the change in the electrode potential before and after the antigen-antiboby reaction. The response time of immunosensor prepared with two anti-IgG electrodes is less than 6 min. The correlation coefficients of the response to hlgG are 0.997 and 0. 995 in the concentration range of 0.2 - 2.0 μg/L with the detection limit of 0. 1 μg/L, respectively. The relative standard deviation （RSD） is less than 6.2% （ n = 5 ） and the recovery is in the range of 93% - 108% for the determination of human serum. The immunosensor can be repeatedly used after activation of regenerative reagent and its activation may maintain more than 30 days in the circumstance of4℃.