A Highly Sensitive Silicon Nanowire Array Field Effect Transistor Biosensor for Detecting HBV-DNA and AFP

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Biosensors

Background:

• Chronic hepatitis B is a significant health concern requiring early diagnosis.
• Hepatitis B virus (HBV) and Alpha-fetoprotein (AFP) are critical biomarkers for chronic hepatitis B detection.
• Current diagnostic methods may lack the sensitivity or real-time capabilities needed for optimal patient management.

Purpose of the Study:

• To develop a highly sensitive, real-time, and low-cost biosensor for the joint detection of HBV and AFP.
• To utilize silicon nanowire array field-effect transistors (SiNW-array FETs) for enhanced biomarker detection.
• To establish a foundation for improved clinical diagnostics of chronic hepatitis B.

Main Methods:

• Fabrication of SiNW-array FETs using micro-nano fabrication techniques like self-limiting oxidation and anisotropic etching.
• Surface modification of SiNWs for specific binding of HBV-DNA fragments and AFP.
• Characterization of SiNW morphology, electrical properties, and biosensor performance.

Main Results:

• Uniform SiNW diameters and a strong output signal with a high signal-to-noise ratio were achieved.
• The SiNW-array FET demonstrated high sensitivity and specificity for HBV-DNA and AFP.
• Ultratlow detection limits of 0.1 fM for HBV-DNA and 0.1 fg/mL for AFP were obtained.
• Successful detection of HBV-DNA in serum samples was achieved, validating clinical applicability.

Conclusions:

• The developed SiNW-array FET biosensor offers a promising platform for sensitive and real-time joint detection of HBV and AFP.
• This technology can significantly aid in the early diagnosis and management of chronic hepatitis B.
• The biosensor's performance in serum samples supports its potential for clinical application.