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Updated: Jun 26, 2026
07:51
Development and Functionalization of Electrolyte-Gated Graphene Field-Effect Transistor for Biomarker Detection
Published on: February 1, 2022
Glutamate sensing with enzyme-modified floating-gate field effect transistors.
D Braeken1, D R Rand, A Andrei
1IMEC v.z.w., Kapeldreef 75, 3001 Leuven, Belgium. dries.braeken@imec.be
Biosensors & Bioelectronics
|January 22, 2009
Summary
This study presents a novel biosensor for detecting neurotransmitter release. The enzyme-modified field-effect transistor (ENFET) offers fast, selective glutamate detection, crucial for understanding brain signaling.
Area of Science:
- Neuroscience
- Biotechnology
- Sensor Technology
Background:
- Neurotransmitter release is vital for brain communication.
- Accurate detection of neurotransmitter release is challenging due to low molecule counts and rapid diffusion.
- Microelectronic biosensors offer potential for sensitive and selective analyte detection.
Purpose of the Study:
- To develop a sensitive and selective biosensor for in vitro neurotransmitter detection.
- To optimize surface chemistry for maximal enzyme loading and stability.
- To demonstrate the potential for detecting glutamate release.
Main Methods:
- Fabrication of a floating-gate field-effect transistor (FET) coated with glutamate oxidase (GLOD).
- Optimization of surface chemistry using poly-L-lysin and glutaraldehyde.
- Characterization using quartz crystal microbalance and colorimetric assays.
- Performance evaluation including detection limit and selectivity.
Main Results:
- Optimized surface chemistry achieved maximal enzyme loading and demonstrated stability for over one month.
- The GLOD-coated FET biosensor achieved a glutamate detection limit of 10(-7) M.
- The sensor exhibited high selectivity for glutamate.
Conclusions:
- The developed GLOD-coated FET biosensor is a promising tool for in vitro glutamate detection.
- This technology can be extended for the detection of other neurotransmitters.
- The biosensor advances in situ monitoring of synaptic transmission.
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