Redox Sensor Array with 23.5-μm Resolution for Real-Time Imaging of Hydrogen Peroxide and Glutamate Based on...

Area of Science:

• Electrochemistry
• Neuroscience
• Biosensing

Background:

• Understanding spatio-temporal neurotransmitter distribution is crucial for neuroscience.
• Existing techniques often lack the required resolution or real-time capabilities.

Purpose of the Study:

• To develop a high-resolution potentiometric redox sensor array for neurotransmitter detection.
• To demonstrate the feasibility of this sensor array for real-time bioimaging.

Main Methods:

• Fabrication of a 128x128 pixel potentiometric sensor array with 23.5-µm resolution.
• Utilized charge-transfer-type potentiometric sensors with gold electrodes.
• Investigated sensing characteristics using redox reactions (K3Fe(CN)6/K4Fe(CN)6) and enzyme-based detection (hydrogen peroxide, glutamate).

Main Results:

• Achieved a redox sensitivity of 49.9 mV/dec.
• Detected hydrogen peroxide with a sensitivity of 44.7 mV/dec and a limit of detection (LOD) of 1 µM.
• Successfully measured glutamate with similar sensitivity and LOD, and visualized its real-time distribution.

Conclusions:

• The developed potentiometric sensor array offers high-resolution spatio-temporal neurotransmitter detection.
• The device shows significant potential as a bioimaging technique for neuroscience research.
• Further improvements in electron mediator oxidation state could lower the LOD.