Wang Yang, Sun Shuai, Luo Jinping, Xiong Ying, Ming Tao, Liu Juntao, Ma Yuanyuan, Yan Shi, Yang Yue, Yang Zhugen, Reboud Julien, Yin Huabing, Cooper Jonathan M, Cai Xinxia
State Key Laboratory of Transducer Technology, Institute of Electronics, Chinese Academy of Sciences, Beijing, 100190 China.
University of Chinese Academy of Sciences, Beijing, 100190 China.
Microsyst Nanoeng. 2020 May 18;6:32. doi: 10.1038/s41378-020-0146-2. eCollection 2020.
In this work, an electrochemical paper-based aptasensor was fabricated for label-free and ultrasensitive detection of epidermal growth factor receptor (EGFR) by employing anti-EGFR aptamers as the bio-recognition element. The device used the concept of paper-folding, or origami, to serve as a valve between sample introduction and detection, so reducing sampling volumes and improving operation convenience. Amino-functionalized graphene (NH-GO)/thionine (THI)/gold particle (AuNP) nanocomposites were used to modify the working electrode not only to generate the electrochemical signals, but also to provide an environment conducive to aptamer immobilization. Electrochemical characterization revealed that the formation of an insulating aptamer-antigen immunocomplex would hinder electron transfer from the sample medium to the working electrode, thus resulting in a lower signal. The experimental results showed that the proposed aptasensor exhibited a linear range from 0.05 to 200 ngmL ( = 0.989) and a detection limit of 5 pgmL for EGFR. The analytical reliability of the proposed paper-based aptasensor was further investigated by analyzing serum samples, showing good agreement with the gold-standard enzyme-linked immunosorbent assay.
在本研究中，通过使用抗表皮生长因子受体（EGFR）适配体作为生物识别元件，制备了一种基于电化学纸的适配体传感器，用于对EGFR进行无标记超灵敏检测。该装置采用折纸概念作为样品引入和检测之间的阀门，从而减少进样体积并提高操作便利性。氨基功能化石墨烯（NH-GO）/硫堇（THI）/金颗粒（AuNP）纳米复合材料用于修饰工作电极，不仅用于产生电化学信号，还用于提供有利于适配体固定的环境。电化学表征表明，绝缘的适配体-抗原免疫复合物的形成会阻碍电子从样品介质转移到工作电极，从而导致信号降低。实验结果表明，所提出的适配体传感器对EGFR的线性范围为0.05至200 ng/mL（r = 0.989），检测限为5 pg/mL。通过分析血清样品进一步研究了所提出的基于纸的适配体传感器的分析可靠性，结果表明与金标准酶联免疫吸附测定法具有良好的一致性。
