Highly sensitive glucose sensors based on enzyme-modified whole-graphene solution-gated transistors

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Noninvasive glucose detection is crucial for diabetes mellitus management.
• Conventional electrochemical glucose sensors lack the required sensitivity for practical noninvasive applications.
• Development of highly sensitive and selective glucose sensors is an ongoing challenge.

Purpose of the Study:

• To develop highly sensitive glucose sensors for noninvasive diabetes detection.
• To enhance the sensitivity of glucose sensors using whole-graphene solution-gated transistors.
• To explore the potential of graphene-based transistors as a versatile biosensing platform.

Main Methods:

• Fabrication of whole-graphene solution-gated transistors.
• Modification of graphene gate electrodes with glucose oxidase enzyme.
• Co-modification of graphene gates with platinum nanoparticles to enhance electrocatalytic activity.
• Investigation of the sensing mechanism involving H2O2 generated from glucose oxidation.

Main Results:

• Achieved significantly improved sensitivity in glucose sensors.
• Demonstrated detection limits as low as 0.5 μM, suitable for body fluid analysis.
• Observed transconductances two orders of magnitude higher than conventional silicon field-effect transistors.
• Confirmed good selectivity for glucose detection.

Conclusions:

• Whole-graphene solution-gated transistors modified with glucose oxidase and Pt nanoparticles represent a high-performance sensing platform.
• The developed sensors are sensitive enough for non-invasive glucose monitoring in body fluids.
• The low-cost fabrication and high performance suggest broad applicability for various biosensing applications.