Electrical probing of COVID-19 spike protein receptor binding domain via a graphene field-effect transistor

Xiaoyan Zhang; Qige Qi; Qiushi Jing; Shen Ao; Zhihong Zhang; Mingchao Ding; Muhong Wu; Kaihui Liu; Weipeng Wang; Yunhan Ling; Zhengjun Zhang; Wangyang Fu

arXiv · 2003.12529

Electrical probing of COVID-19 spike protein receptor binding domain via a graphene field-effect transistor

Xiaoyan Zhang·Qige Qi·Qiushi Jing·Shen Ao·Zhihong Zhang·Mingchao Ding·Muhong Wu·Kaihui Liu·Weipeng Wang·Yunhan Ling·Zhengjun Zhang·Wangyang Fu

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Abstract

Here, in an effort towards facile and fast screening/diagnosis of novel coronavirus disease 2019 (COVID-19), we combined the unprecedently sensitive graphene field-effect transistor (Gr-FET) with highly selective antibody-antigen interaction to develop a coronavirus immunosensor. The Gr-FET immunosensors can rapidly identify (about 2 mins) and accurately capture the COVID-19 spike protein S1 (which contains a receptor binding domain, RBD) at a limit of detection down to 0.2 pM, in a real-time and label-free manner. Further results ensure that the Gr-FET immunosensors can be promisingly applied to screen for high-affinity antibodies (with binding constant up to 2*10^11 M^-1 against the RBD) at concentrations down to 0.1 pM. Thus, our developed electrical Gr-FET immunosensors provide an appealing alternative to address the early screening/diagnosis as well as the analysis and rational design of neutralizing-antibody locking methods of this ongoing public health crisis.

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Xiaoyan Zhang, Qige Qi, Qiushi Jing, Shen Ao, Zhihong Zhang, Mingchao Ding, Muhong Wu, Kaihui Liu, Weipeng Wang, Yunhan Ling, Zhengjun Zhang, Wangyang Fu. 2020-03-27. Electrical probing of COVID-19 spike protein receptor binding domain via a graphene field-effect transistor. https://arxiv.org/abs/2003.12529

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