纳米金修饰玻碳电极固载抗体电位型白喉类毒素免疫传感器的研究

Potentiometric Diphtheria Immunosensor Based on a Glassy Carbon Electrode Modified with Colloidal Gold and Anti-Diph

将巯基乙胺 (AET)固载到玻碳电极 (GCE)表面 ,进而化学吸附纳米金 (NG) ,并通过半胱氨酸 (Cys)用戊二醛 (GA)作交联剂将白喉抗体 (anti Diph)固定在玻碳电极上 ,从而制得高灵敏电位型白喉类毒素 (Diph)免疫传感器 .通过循环伏安法考察了电极表面的电化学特性 ,并对该免疫传感器的性能进行了详细的研究 .该传感器对白喉类毒素检测的线性范围是 2 4～ 60 0ng·mL-1,斜率为 3 8.9mV/decade ,线性相关系数为 0 .9979,检出限为 5 .2ng·mL-1,并将其用于生物制品中白喉类毒素的检测 。

A novel potentiometric immunosensor for the detection of diphtheria antigen (Diph) has been developed by means of self-assembly to covalently immobilized diphtheria antibody (anti-Diph) on a glassy carbon electrode. At first, the modification of glassy carbon electrode (GCE) with nano-gold (NG) by chemical adsorption of 2-aminoethane thoil (AET) was achieved, and then cysteine (Cys) molecules were adsorbed on the nano-gold surface. Finally, diphtheria antibodies were covalently immobilized on the electrode by glutaraldehyde ( GA). The modification procedure was electrochemically monitored by characterization of the electrode surface. The performance and influencing factors of the resulting immunosensor were studied in detail. The resulting immunosensor exhibited fast potentiometric response to Diph and the detection limit of the immunosensor was from 24 ng (.) mL(-) 1 to 600 ng (.) mL(-1) with correlation coefficient of 0.9979 and a detection limit of 5.2 ng (.) mL(-1). More than 91.3% of the results of the bioproduced samples obtained by this method were in agreement with those by enzyme-linked immunosorbent assay (ELISA).