Breath alcohol sensor based on hydrogel-gated graphene field-effect transistor

Area of Science:

• Biosensor technology
• Graphene field-effect transistors
• Electrochemical sensing

Background:

• Traffic accidents are a major concern, with drunk driving being a significant contributing factor.
• Effective breath alcohol detection is crucial for road safety and public health.
• Existing biosensors often lack portability and sensitivity for real-time applications.

Purpose of the Study:

• To develop a highly sensitive and portable breath alcohol biosensor.
• To utilize chlorella-derived carbon nanosheets and alcohol oxidase for enhanced sensing.
• To demonstrate the application of a hydrogel-gated graphene field-effect transistor (HGGT) for alcohol detection.

Main Methods:

• Construction of a hydrogel-gated graphene field-effect transistor (HGGT) biosensor.
• Functionalization of the HGGT with chlorella-derived layered carbon nanosheets (CNs) and alcohol oxidase (AOx).
• Investigation of the sensing mechanism involving alcohol oxidation and hydrogen peroxide electrocatalysis.

Main Results:

• The HGGT-based alcohol sensor demonstrated excellent sensitivity with a low detection limit of 1 μM (0.046 ppm).
• The sensor was successfully applied for breath alcohol testing after drinking.
• The hydrogel electrolyte enhanced sensor portability and facilitated enzyme/nanomaterial integration.

Conclusions:

• The developed HGGT biosensor offers a promising platform for accurate and real-time breath alcohol detection.
• The sensor's portability and sensitivity make it suitable for drunk driving inspections.
• This technology shows potential for developing biosensors for various other analytes.