氧化铱膜增强的阻抗免疫传感器快速检测癌胚抗原

本文研制了一种基于IrO_x薄膜的阻抗型免疫传感器用于简单、快速灵敏地检测人血清中癌胚抗原（CEA）浓度。采用在金电极表面同时电化学沉积IrO_x薄膜和蛋白A（PA），构建成传感界面介导抗体的定向固定。着重考察了传感检测的最优条件：电化学沉积时间及PA的浓度。在最优化的实验条件下，测得CEA 的浓度为36.2 - 460.0 ng/mL，检测下限为28.0 ng/mL。同时，采用该分析方法检测临床样品，并与化学发光免疫分析法进行了比较，实验结果表明该阻抗型免疫分析方法可推广于临床实验室CEA的免疫检测。     

纳米金-蛋白A介导抗体定向固定的压电传感及电化学特性研究

以纳米金为载体标记蛋白A(PA),用于介导抗体在压电石英晶体金电极表面的定向固定化.以补体C_1q抗体为模型,采用压电传感技术实时监察了此敏感界面的免疫反应过程,并考察了与补体C_1q免疫反应的压电响应性能.金标PA固定抗体的方法与传统的直接PA固定化方法相比较,具有传感界面无需活化,固定抗体的免疫活性高等优点,可对相应抗原进行高灵敏的压电免疫检测.分别利用循环伏安和电化学交流阻抗技术对金标PA固定抗体及其免疫反应的动力学过程进行了表征.     

Iridium Oxide Film-Enhanced Impedance Immunosensor for Rapid Detection of Carcinoembyronic Antigen

A simple, rapid and sensitive impedance immunosensor based on iridium oxide （IrOx） thin film for the detection of carcinoembyronic antigen （CEA） in human sera has been proposed. Gold electrode was electrochemically modified with IrOx thin film and simultaneously functionalized with protein A （PA） to bind anti-CEA antibodies in an orientated way. It has been found that the antibody loading amount was dependent on the PA concentration and the deposition time of IrOx matrix. Under the optimized experimental conditions, the electron transfer resistances obtained were linearly related to the CEA concentration ranging from 36.2 to 460.0 ng/mL, with a detection limit of 28.0 ng/mL. Analytical results of clinical samples from cancer patients show that the proposed immunoassay is reasonably comparable with the chemiluminescence immunoassay （CLIA）, indicating the feasibility of using the proposed method for CEA immunoassay in clinical laboratory.