Electrolyte-gated amorphous IGZO transistors with extended gates for prostate-specific antigen detection

Area of Science:

• Materials Science
• Biomedical Engineering
• Electronics

Background:

• Prostate-specific antigen (PSA) testing is crucial for prostate cancer diagnosis and screening.
• Existing PSA detection methods are limited by cost, time, and stability.
• There is a need for rapid, portable, and stable PSA detection systems.

Purpose of the Study:

• To develop a portable biosensor for real-time, instant PSA detection.
• To utilize electrolyte-gated amorphous indium gallium zinc oxide (a-IGZO) transistors for enhanced sensitivity and stability.
• To establish a point-of-care system for prostate cancer screening.

Main Methods:

• Fabrication of a portable biosensor using a-IGZO transistors with an extended gate.
• Employment of liquid-free ionic conductive elastomer (ICE) as the gate dielectric.
• Integration of a separate, biodegradable sensing pad for stable biomolecular interaction.

Main Results:

• Achieved real-time PSA detection at low operating voltage (<2 V).
• Demonstrated a small subthreshold swing (<0.5 V dec-1) and high on-state current (∼4 × 10-4 A).
• Exhibited a linear response to PSA concentrations (1 fg mL-1 to 10 pg mL-1) with a low detection limit (400 ag mL-1) and rapid detection time (∼5.1 s).
• Maintained superior electronic performance for over six months.

Conclusions:

• The developed biosensor enables instant, sensitive, and stable PSA detection.
• Electrolyte-gated transistors show significant potential for point-of-care diagnostics.
• This technology can advance clinical screening, healthcare diagnostics, and biological management.