Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, PR China.
Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, PR China; Hubei Provincial Center for Disease Control and Prevention, Wuhan 430072, PR China.
Biosens Bioelectron. 2018 Jan 15;99:186-192. doi: 10.1016/j.bios.2017.07.035. Epub 2017 Jul 14.
Point-of-care detection of human enterovirus 71 (EV71), the major pathogen that causes hand, foot, and mouth disease (HFMD) among children, is urgently needed for early diagnosis and control of related epidemics. A colorimetric and electrochemical immunosensor for point-of-care detection of EV71 has been developed based on dual-labeled magnetic nanobeads amplification. The dual-labeled magnetic nanobeads (DL-MBs) are fabricated by simultaneous immobilization of EV71 monoclonal antibody (mAb) and horseradish peroxidase (HRP) on magnetic nanobeads. By capturing EV71 virions in 20μL sample on mAb modified AuNPs-coated ITO electrode and subsequently binding with DL-MBs, with the addition of TMB and HO, colorimetric signals corresponding to EV71 with a concentration of 1.0ngmL can be directly read out by naked eyes, making it possible towards point-of-care detection of the virus. Furthermore, on the reduction of oxidized TMB on the electrode, electrochemical signal can be detected in the same detection cell without solution transfer, with a detection limit of 0.01ngmL. Validated with clinical samples, the colorimetric and electrochemical immunosensor shows a complete consistency with reverse transcription-polymerase chain reaction (RT-PCR) results. So far as we know, this is the first report on EV71 detection using electrochemical method. The merits of this assay, including high sensitivity, ability for colorimetric detection and easy to operation, ensure a promising future in point-of-care diagnostics of virus related diseases.
用于手足口病（HFMD）的病原体肠道病毒 71 型（EV71）的即时检测对于早期诊断和相关传染病的控制非常重要。本研究基于双标记磁珠放大，开发了一种用于 EV71 即时检测的比色和电化学免疫传感器。双标记磁珠（DL-MBs）通过将 EV71 单克隆抗体（mAb）和辣根过氧化物酶（HRP）同时固定在磁珠上制备。通过在 mAb 修饰的 AuNPs 涂覆 ITO 电极上捕获 20μL 样品中的 EV71 病毒粒子，随后与 DL-MBs 结合，加入 TMB 和 HO，可以直接通过肉眼读取对应于 1.0ngmL 的 EV71 的比色信号，从而实现对病毒的即时检测。此外，在电极上还原氧化的 TMB 时，无需溶液转移即可在同一检测池中检测到电化学信号，检测限为 0.01ngmL。通过临床样本验证，比色和电化学免疫传感器与逆转录-聚合酶链反应（RT-PCR）结果完全一致。据我们所知，这是首次使用电化学方法检测 EV71。该检测方法具有高灵敏度、比色检测能力和易于操作的优点，有望在病毒相关疾病的即时诊断中得到应用。
