基于铕配合物与石墨烯复合材料的ECL免疫传感器

ECL Immunosensor Based on Composite of Eu-complex and Graphene

基于自行制备的Eu(Ⅲ)/氨基化石墨烯复合材料,构建了一种新型的电致化学发光免疫传感器,并应用于人免疫球蛋白的检测。制备复合材料时,二乙基三胺五乙酸(DTPA)作为螯合剂,通过脱水缩合反应连接在二维的氨基化石墨烯片层表面。随之,铕(Eu(Ⅲ))与DTPA作用,螯合在石墨烯表面。由于铕关键的作用,所得的材料显示出稳定的强烈的电致化学发光性能。配合氨基化石墨烯优越的电化学性能,大的比表面积,良好的分散性,该传感器实现了对人免疫球蛋白的灵敏检测,线性范围是0.5~14ng·mL^(-1),检测限为100pg·mL^(-1)。除此之外,该免疫传感器显示出良好的选择性、重现性和稳定性,表现出用于临床检测的良好潜力。

In this study, a novel ECL immunosensor was established to detect human immunoglobulin （IgG） as a model target analyte, based on Eu（ Ⅲ ）/NH2-graphene composites. To build the composite and the sensor, diethylene triamine pentacetate acid （DTPA）, as a che- lating agent, was bonded to the two-dimensional NH2-graphene sheets, via the dehydration condensation reaction. Eu（Ⅲ） was then chelated to the sheets to form a composite, exhibiting strong and stable cathodic electrochemiluminescenee （ECL） activity due to the important roles of Eu（Ⅲ）. NH2-graphene has excellent electrochemical properties, large surface area, good dispersion in water, which are good for the immobilization of antibody. The ECL immunosensor was found to give a sensitive response to IgG in a linear range of 0. 5-14 ng · mL-1 with a detection limit of 100 pg · mL-1. Additionally, the proposed immunosensor showed high specificity, good reproducibility, and stability, which might be promising for clinical application.