基于巯基自组装单层膜技术的补体C_3压电免疫传感器的研究

A Piezo-Immunosensor Based on the Thiol-Terminated SAMs Technique for the Detection of Human Complement C_3

本文采用自组装单层膜(SAMs)技术在压电石英晶振金电极表面组装巯基丙酸SAMs,以盐酸1乙基3(3二甲基氨基丙基)碳二亚胺(EDC)和N羟基琥珀酰亚胺(NHS)作偶联剂共价固定补体C3抗体,研制了一种检测人血清中补体C3成分的压电免疫传感器。研究了巯基丙酸的自组装和抗体的固定化条件,考察了晶振固定抗体后的液相振荡行为和检测特性。并利用压电传感装置的实时监测功能,研究了巯基丙酸在金电极表面的自组装成膜过程和补体C3免疫反应动力学,获得了重要的动力学依据和参数。传感器检测补体C3的线性范围为2.34～23.2μg/mL。将传感器用于临床样品的检测,所得结果与酶联免疫吸附法基本一致。

In this paper, a self-assembled monolayer (SAM) of mercaptopropionic acid (MPA) was constructed on the gold electrode surface of piezoelectric crystal and then activated by ECD and NHS to covalently bind antibodies for the determination of complement C_3 in human serum. The main experimental conditions were investigated including the formation of MPA-SAMs and the immobilization of antibodies. The resonant behavior of the crystal in liquid phase and the detection characteristics of the immunosensor were studied in detail. Moreover, the self-assembly process of MPA on the gold electrode and the immunoreactive kinetic were explored by use of the real-time monitoring device. The dynamic parameter of reaction rate constants ( K _f ) was obtained. Complement C_3 could be detected in the linear range of 2.34~23.2 μg/mL. The new immunoassay system was evaluated for detecting several clinical specimens. The results obtained by the piezo-immunoassay were in satisfactory agreement with those given by the classical ELISA method.