Peptide-based simple detection of SARS-CoV-2 with electrochemical readout

Coronavirus disease 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is considered one of the worst pandemic outbreaks worldwide. This ongoing pandemic urgently requires rapid, accurate, and specific testing devices to detect the virus. We report a simple electrochemical biosensor based on a highly specific synthetic peptide to detect SARS-CoV-2 Spike protein. Unlike other reported electrochemical biosensors involving nanomaterials or complex approaches, our electrochemical platform uses screen-printed gold electrodes functionalized with the thiolated peptide, whose interaction with the Spike protein is directly followed by Electrochemical Impedance Spectroscopy. The electrochemical platform was Spike protein concentration-dependent, with high sensitivity and reproducibility and a limit of detection of 18.2 ng/mL when tested in Spike protein commercial solutions and 0.01 copies/mL in lysed SARS-CoV-2 particles. The label-free biosensor successfully detected the Spike protein in samples from infected patients straightforwardly in only 15 min. The simplicity of the proposed format combined with an on-demand designed peptide opens the path for detecting other pathogen-related antigens. (C) 2022 Elsevier B.V. All rights reserved.

Automated summary

This article describes a novel and simple electrochemical biosensor for rapid detection of the Spike protein of the novel coronavirus. The biosensor exhibits high sensitivity and reproducibility, and can directly detect the protein in patient samples within 15 minutes.