Electrochemical Detection of SARS-CoV‑2 Spike Protein: A Fast and Effective Pathway to Pandemic Diagnostics

Electrochemical sensors could potentially serve as a key analytical tool for the reliable detection of viruses and the prevention of pathogen transmission, particularly during pandemics such as COVID-19. This study aimed to develop a novel, rapid, and low-cost electrochemical aptasensor as a proof-of-concept platform for the detection of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). The proposed design utilizes a streptavidin-modified screen-printed carbon electrode. To ensure aptamer-protein interaction, three various biotinylated aptamers were developed and studied. Based on the obtained results, Aptamer 3 was chosen for further analysis. The developed aptasensor was characterized using electrochemical methods such as cyclic voltammetry, electrochemical impedance spectroscopy, and differential pulse voltammetry. The proposed sensor demonstrated a linear range from 0.05 to 2 μM, a sensitivity of 8.03 μA μM^-1, high reproducibility with the standard deviation up to 10%, and a limit of detection (0.48 μM). These results highlight a successful proof-of-concept electrochemical platform for the detection of the SARS-CoV-2 spike protein.