School of Public Health and Management, Chongqing Medical University, Chongqing, 400016, China; Health Management Department, Zunyi Medical and Pharmaceutical College, Zunyi, Guizhou, 563006, China.
School of Public Health and Management, Chongqing Medical University, Chongqing, 400016, China.
Talanta. 2022 Oct 1;248:123605. doi: 10.1016/j.talanta.2022.123605. Epub 2022 May 28.
In this work, a brief electrochemical aptasensor was developed for highly sensitive detection of SARS-CoV-2 antigen utilizing an aptamer-binding induced multiple hairpin assembly strategy for signal amplification. In the presence of SARS-CoV-2, a pair of aptamers was brought in a close proximity according to the aptamer-protein antigen binding, which initiated strand displacement reaction thereby triggering a multiple hairpin assembly to obtain long linear DNA concatemers on the electrode surface. As the fabricated hairpin probes were labeled with biotin, massive streptavidin-alkaline phosphatases (ST-ALP) could be further introduced on the electrode interface via biotin-streptavidin interaction thus generating strong electrochemical signal in electrolyte solution containing 1-naphthol phosphate. Benefiting from the non-enzymatic multiple hairpin assembly signal amplification strategy, the designed aptasensor for SARS-CoV-2 spike protein detection exhibited the wide linear range from 50 fg·mL to 50 ng·mL and low detection limit of 9.79 fg·mL. Meaningfully, this proposed electrochemical assay provided a potential application for the point of care analysis of viral diseases under ambient temperature.
在这项工作中，开发了一种简短的电化学适体传感器，用于利用适体结合诱导的多重发夹组装策略进行 SARS-CoV-2 抗原的高灵敏度检测，以进行信号放大。在存在 SARS-CoV-2 的情况下，根据适体-蛋白抗原结合，一对适体紧密接近，引发链置换反应，从而触发多重发夹组装，在电极表面获得长线性 DNA 串联体。由于制备的发夹探针被生物素标记，因此可以通过生物素-链霉亲和素相互作用进一步在电极界面上引入大量链霉亲和素-碱性磷酸酶（ST-ALP），从而在含有 1-萘酚磷酸盐的电解质溶液中产生强电化学信号。得益于非酶的多重发夹组装信号放大策略，用于 SARS-CoV-2 刺突蛋白检测的设计适体传感器表现出从 50 fg·mL 至 50 ng·mL 的宽线性范围和 9.79 fg·mL 的低检测限。有意义的是，该电化学分析方法为在环境温度下进行病毒疾病的即时检测分析提供了一种潜在的应用。
