Abstract

Low-cost biosensors that can rapidly and widely detect viruses are critical for faster diagnosis and treatment decision-making, especially for infections. The commonly used field-effect transistor is sensitive to the biomarker's detection but struggles with precise detection, particularly of nontargets such as ions and proteins. To overcome this limitation, we developed a field-effect transistor biosensor design based on MXene-graphene materials to increase the accuracy and sensitivity of virus detection. Based on the hybridization process between two complementary DNA strands, single-stranded nucleic acids were immobilized on the sensing surface via 3-aminopropyltriethoxysilane and glutaraldehyde to capture the nucleic acids of the target virus. The addition of the MXene layer provides a reduced system capacitance and tuned bandgap compared to that of stand-alone graphene. This tuning can significantly enhance the sensitivity of the developed platform. The SARS-CoV-2 and its Omicron variant were used to validate the developed biosensor. The results showed high accuracy with detection limits as low as 1 x 10-21 and 1 x 10-22 mol/L (60.2 and 6.02 copies/L equivalently), for SARS-CoV-2 and its Omicron variant, respectively. Twenty-four clinical tests were also conducted using the developed ssDNA-MXene-graphene biosensors with patients' nasopharyngeal swab samples. The biosensor's results closely matched those of the reverse transcription-quantitative polymerase chain reaction (RT-qPCR) detection but with a significantly shorter detection time, demonstrating the sensors' real-time, in situ, practical application. This result also demonstrates the promising future of MXene-based biosensors for virus detection using nucleic acid probes.

Department(s)

Biological Sciences

Second Department

Electrical and Computer Engineering

Third Department

Chemistry

Comments

National Science Foundation, Grant 2414716

Keywords and Phrases

clinical tests; field-effect transistor biosensor; Omicron variant; SARS-CoV-2; ssDNA-MXene-graphene

International Standard Serial Number (ISSN)

2574-0970

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2025 American Chemical Society, All rights reserved.

Publication Date

01 Jan 2024

Share

 
COinS