【摘要】 共固定氯代邻菲啰啉双核铜配合物(Cu2(phen)2Cl2(μ-Cl)2,简称Cu2L)和包被三聚氰胺抗体(antiMA)的Fe3O4/Au胶(简称纳米磁珠)于丝网印刷电极(SPCE)表面,构建了一种测定牛奶中三聚氰胺(简称MA)含量的安培免疫传感器。当该传感器在含MA溶液中温育时,MA和同时加入的HRP标MA二抗(HRP-antiMAII),与电极表面的antiMA形成三元免疫复合物。该复合物上的HRP能催化H2O2还原,并经过Cu2L传导在电极表面形成电流,电流强度I与MA浓度在0.5～40和60～100ng/mL范围内呈线性关系,检测限为0.25ng/mL。在pH6.2的PBS底液中,该传感器制作简单、可抛弃,对MA检测时间小于20min,灵敏度为1μA.ng-1mL,明显高于酶联免疫吸附(ELISA)法;可实现牛奶中MA免分离现场分析。更多还原

【Abstract】 An electroimmunosensor for the determination of melamine(MA) in milk was proposed, which was prepared by co-immobilizing melamine antibody (anti MA),chloro-phenanthroline binuclear copper(Cu2(phen)2Cl2(μ-Cl)2,Cu2L) and HRP marked Fe3O4/Au colloid nano-particles coating on one carbon screen printing electrode. The detection of MA is based on the principle of sandwich immunoassay. When the sensor was incubated in the solution containing MA, HRP labeled antibody MA II (HRP-anti MA II). Then the sandwich immunocomplexes gradually generated on the electrode surface.The current increase results from the enhanced catalytic current of H2O2 reduction with the help of HRP labeled immune-compound, which leads to a linear increase of the catalytic efficiency of CuL by H2O2 in two MA concentration ranges from 1~40 and 60~100 ng/mL with the detection limit of 0.25 ng/mL (3σ). The proposed method needs neither separation nor washing up step, which simplifies the immunoassay procedure by ELISA method, shortens the analytical time to 20 mins, and the sensitivity was 1 μA·ng-1 mL, which provides a new promising platform to diagnosing the melanmine in milk.更多还原