Electrochemical Sensors Based on Dirac Semimental NiTe₂ in the Detection of SARS-CoV-2

In the present study, a topological semimetal NiTe₂-based electrochemical biosensor was designed and fabricated, leveraging the material's inherent topological surface state and conductive bulk properties. The NiTe₂ electrode was fabricated via mechanical exfoliation from a high-quality NiTe₂ single crystal. Owing to its robust layered structure and unique Dirac surface states, the topological semimetal NiTe₂ facilitates rapid electron transfer at the electrode surface, thereby enhancing the sensor's performance. The developed biosensor showed a linear response range for DNA concentrations spanning from 10^-15 to 10^-7 M, with a detection limit as low as 10^-16 M. In contrast, its detection response toward RNA was more sensitive, covering a concentration range of 10^-18 to 10^-15 M. Furthermore, this sensor was employed for the detection of synthetic SARS-CoV-2 pseudovirus at a concentration of 1000 copies/mL. The results demonstrated that the sensor could effectively differentiate between negative and positive samples, exhibiting excellent sensitivity, specificity, and stability. Consequently, the NiTe₂-based biosensor possesses significant potential for application in the clinical diagnosis of SARS-CoV-2 pathogens and other acute infectious diseases.