Intelligence and Information Engineering College of Tangshan University, Tangshan, 063000, China.
General Cargo Branch of Qinhuangdao Port Company Limited, Qinhuangdao, 066000, China.
Biosens Bioelectron. 2019 Jun 15;135:1-7. doi: 10.1016/j.bios.2019.03.063. Epub 2019 Apr 5.
A paper-based electrochemical immunosensor was developed for the detection of cancer antigen 125 (CA125) by screen-printing technique. The reduced graphene oxide/thionine/gold nanoparticles (rGO/Thi/AuNPs) nanocomposites were compounded and coated onto the working electrode of immunosensor for CA125 antibody (anti-CA125) immobilization and detection signal amplification. The detection principle was based on the fact that the immunocomplex formed by specify binding of CA125 antibody and antigen could reduce the current response of thionine, which was proportional to the corresponding concentration of CA125 antigen. The immunoassay results showed that the linear range of CA125 was from 0.1 U mL to 200 U mL with the limit of detection (LOD) of 0.01 U mL at signal to noise of 3. Quality control serum samples measured by our proposed immunosensor showed acceptable agreement with traditional ELISA method with the relative error less than 8.05%. The immunosensor exhibited good electrochemical performance with high reproducibility, reliability, stability and accuracy. The proposed immunosensor could be used for the determination of CA125 and had the potential for point-of-care testing (POCT) of other tumor marker.
一种基于纸质的电化学免疫传感器通过丝网印刷技术被开发用于检测癌抗原 125（CA125）。还原氧化石墨烯/硫堇/金纳米粒子（rGO/Thi/AuNPs）纳米复合材料被复合并涂覆到免疫传感器的工作电极上，用于 CA125 抗体（抗-CA125）的固定化和检测信号放大。检测原理基于这样一个事实，即 CA125 抗体和抗原的特异性结合形成的免疫复合物可以降低硫堇的电流响应，其与相应的 CA125 抗原浓度成正比。免疫分析结果表明，CA125 的线性范围为 0.1 U mL 至 200 U mL，检测限（LOD）为 0.01 U mL，信噪比为 3。用我们提出的免疫传感器测量的质控血清样品与传统 ELISA 方法具有可接受的一致性，相对误差小于 8.05%。该免疫传感器表现出良好的电化学性能，具有高重现性、可靠性、稳定性和准确性。该免疫传感器可用于 CA125 的测定，并有可能用于其他肿瘤标志物的即时检测（POCT）。
