The potential application of electrochemical biosensors in the COVID-19 pandemic: A perspective on the rapid diagnostics of SARS-CoV-2

Abstract

Electrochemical biosensors combine the selectivity of electrochemical signal transducers with the specificity of biomolecular recognition strategies. Although they have been broadly studied in different areas of diagnostics, they are not yet fully commercialized. During the COVID-19 pandemic, electrochemical platforms have shown the potential to address significant limitations of conventional diagnostic platforms, including accuracy, affordability, and portability. The advantages of electrochemical platforms make them a strong candidate for rapid point-of-care detection of SARS-CoV-2 infection by targeting not only viral RNA but antigens and antibodies. Herein, we reviewed advancements in electrochemical biosensing platforms towards the detection of SARS-CoV-2 through studying similar viruses.

Keywords: Coronaviruses; Electrochemical signal; Nucleic acid–based detection; Pathogen diagnostics; Recognition element; Serological testing.

Scheme 1

(top) The Novel Coronavirus SARS-CoV-2 illustrated with its components, including the surface proteins and viral RNA. Illustration of various steps to perform (middle) RT-PCR, and (bottom) ELISA-serological tests.

Scheme 2

Electrochemical biosensors can potentially assess various human specimens including finger-prick blood, nasopharyngeal, and saliva samples, for target analytes. The platforms possess (1) a readout device (2) a biosensing chip with sample delivery system and electronic leads to transfer the response of the electrodes to the readout device, (3) electrodes with the corresponding recognition elements of complementary oligonucleotides, antibodies, antigens to detect the target oligonucleotides, antigens, and antibodies, respectively, with a quantifiable current response proportional to the analyte concentration.

Scheme 3

Brief illustration of the electrochemical biosensing platforms through the assay format and electrochemical responses for the detection of RNA/DNA. Panels A to F represent the assay formats for various platforms discussed in this study; A’ to F’ and A’’ show the type of electrochemical responses and how it varies with target concentration ((a) and (b) represents either with target (+target) or without target (–target)); A‴, C’’, D’’ and F’’ are shown in their original scale representing the details on calibration curves and selectivity responses.

Scheme 4

Brief illustration of the electrochemical biosensing platforms the assay format and electrochemical responses for the detection antibody and antigen. Panels A to E represent the assay formats for various platforms discussed in this study; A’ to E’ show the type of electrochemical responses and how it varies with target concentration ((a) and (b) represents either with target (+target) or without target (–target)); A’’, B’’, C’’, C‴, D’’, D‴, and E’’ are shown in their original scale representing the details on calibration curves, multiplexing, and selectivity responses.