Saliva-based COVID-19 detection: A rapid antigen test of SARS-CoV-2 nucleocapsid protein using an electrical-double-layer gated field-effect transistor-based biosensing system

Pin-Hsuan Chen; Chih-Cheng Huang; Chia-Che Wu; Po-Hsuan Chen; Adarsh Tripathi; Yu-Lin Wang

doi:10.1016/j.snb.2022.131415

Saliva-based COVID-19 detection: A rapid antigen test of SARS-CoV-2 nucleocapsid protein using an electrical-double-layer gated field-effect transistor-based biosensing system

Sens Actuators B Chem. 2022 Apr 15:357:131415. doi: 10.1016/j.snb.2022.131415. Epub 2022 Jan 14.

Authors

Pin-Hsuan Chen¹, Chih-Cheng Huang², Chia-Che Wu², Po-Hsuan Chen², Adarsh Tripathi³, Yu-Lin Wang^{1

2}

Affiliations

¹ Department of Power Mechanical Engineering, National Tsing Hua University, Hsinchu 300044, Taiwan (R.O.C.).
² Institute of Nanoengineering and Microsystems, National Tsing Hua University, Hsinchu 300044, Taiwan (R.O.C.).
³ Institute of Molecular Medicine, National Tsing Hua University, Hsinchu 300044, Taiwan (R.O.C.).

Abstract

Facing the unstopped surges of COVID-19, an insufficient capacity of diagnostic testing jeopardizes the control of disease spread. Due to a centralized setting and a long turnaround, real-time reverse transcription polymerase chain reaction (real-time RT-PCR), the gold standard of viral detection, has fallen short in timely reflecting the epidemic status quo during an urgent outbreak. As such, a rapid screening tool is necessitated to help contain the spread of COVID-19 amid the countries where the vaccine implementations have not been widely deployed. In this work, we propose a saliva-based COVID-19 antigen test using the electrical double layer (EDL)-gated field-effect transistor-based biosensor (BioFET). The detection of SARS-CoV-2 nucleocapsid (N) protein is validated with limits of detection (LoDs) of 0.34 ng/mL (7.44 pM) and 0.14 ng/mL (2.96 pM) in 1× PBS and artificial saliva, respectively. The specificity is inspected with types of antigens, exhibiting low cross-reactivity among MERS-CoV, Influenza A virus, and Influenza B virus. This portable system is embedded with Bluetooth communication and user-friendly interfaces that are fully compatible with digital health, feasibly leading to an on-site turnaround, an effective management, and a proactive response taken by medical providers and frontline health workers.

Keywords: Covid-19; Electrical double layer; Field-effect transistor-based biosensors; Rapid antigen tests; SARS-CoV-2.