Two-Dimensional-Material-Based Field-Effect Transistor Biosensor for Detecting COVID-19 Virus (SARS-CoV-2)

The emergence of rapidly expanding infectious diseases such as coronavirus (COVID-19) demands effective biosensors that can promptly detect and recognize the pathogens. Field-effect transistors based on semiconducting two-dimensional (2D) materials (2D-FETs) have been identified as potential candidates for rapid and label-free sensing applications. This is because any perturbation of such atomically thin 2D channels can significantly impact their electronic transport properties. Here, we report the use of FET based on semiconducting transition metal dichalcogenide (TMDC) WSe₂ as a promising biosensor for the rapid and sensitive detection of SARS-CoV-2 in vitro. The sensor is created by functionalizing the WSe₂ monolayers with a monoclonal antibody against the SARS-CoV-2 spike protein and exhibits a detection limit of down to 25 fg/μL in 0.01X phosphate-buffered saline (PBS). Comprehensive theoretical and experimental studies, including density functional theory, atomic force microscopy, Raman and photoluminescence spectroscopies, and electronic transport properties, were performed to characterize and explain the device performance. The results demonstrate that TMDC-based 2D-FETs can potentially serve as sensitive and selective biosensors for the rapid detection of infectious diseases.