Atomically dispersed Mn boosting photoelectrochemical SARS-CoV-2 spike protein immunosensing on carbon nitride

Yunfan Jia; Yun Chen; Li Xu; Junchao Qian; Feng Chen; Yakun Wan; Henan Li; Huaming Li

doi:10.1016/j.jece.2022.108697

Atomically dispersed Mn boosting photoelectrochemical SARS-CoV-2 spike protein immunosensing on carbon nitride

J Environ Chem Eng. 2022 Dec;10(6):108697. doi: 10.1016/j.jece.2022.108697. Epub 2022 Oct 3.

Authors

Yunfan Jia¹, Yun Chen¹, Li Xu¹, Junchao Qian², Feng Chen², Yakun Wan³, Henan Li¹, Huaming Li¹

Affiliations

¹ Key Laboratory for Theory and Technology of Intelligent Agricultural Machinery and Equipment, School of Chemistry and Chemical Engineering, Institute for Energy Research, Jiangsu University, Zhenjiang 212013, China.
² Jiangsu Key Laboratory for Environment Functional Materials, Jiangsu Key Laboratory of Intelligent Building Energy Efficiency, Suzhou University of Science and Technology, Suzhou 215009, China.
³ Shanghai Novamab Biopharmaceuticals Co., Ltd., Shanghai 201318, China.

Abstract

The sudden outbreak of coronavirus disease (COVID-19) triggered by SARS-CoV-2 infection has created a terrifying situation around the world. The spike protein of SARS-CoV-2 can act as an early biomarker for COVID-19. Therefore, controlling the spread of COVID-19 requires a low-cost, fast-response, and sensitive monitoring technique of spike protein. Herein, a photoelectrochemical (PEC) immunosensor for the detection of spike protein was constructed using the nanobody and an Mn (Ⅱ) modified graphitic carbon nitride (Mn/g-C₃N₄). The introduction of atomically dispersed Mn (Ⅱ) can accelerate the effective transfer and separation of photogenerated electron-hole pairs, which significantly boosts PEC performance of g-C₃N₄, thereby improving the detection sensitivity. As a recognition site, nanobody can achieve high-affinity binding to the spike protein, leading to a high sensitivity. The linear detection range of the proposed PEC immunosensor was 75 fg mL^-1 to 150 pg mL^-1, and the limit of detection was calculated to be 1.22 fg mL^-1. This stable and feasible PEC immunosensor would be a promising diagnostic tool for sensitively detecting spike protein of SARS-CoV-2.

Keywords: COVID-19; Carbon nitride; Nanobody; Photoelectrochemical immunosensor; Spike protein.