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10:32
Brain Mapping Using a Graphene Electrode Array
Published on: October 20, 2023
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Deep 2-photon imaging and artifact-free optogenetics through transparent graphene microelectrode arrays
Martin Thunemann1, Yichen Lu2, Xin Liu2
1Department of Radiology, UCSD, La Jolla, CA, 92093, USA.
Nature Communications
|May 24, 2018
Summary
Transparent graphene microelectrodes eliminate light artifacts, enabling simultaneous optical and electrical recordings in neuroscience. This breakthrough integrates multi-photon microscopy and optogenetics with in vivo cortical recordings for comprehensive brain activity analysis.
Area of Science:
- Neuroscience
- Biomedical Engineering
- Materials Science
Background:
- Advances in multi-photon microscopy and optogenetics allow detailed study of neuronal activity.
- Integrating optical methods with electrophysiology is crucial for bridging animal model findings with human brain studies.
- Light-induced artifacts currently hinder combined optical and electrical recording techniques.
Purpose of the Study:
- To develop a technology for artifact-free integration of optical modalities and electrical recordings in neuroscience.
- To enable simultaneous in vivo 2-photon microscopy, optogenetic stimulation, and cortical recordings.
- To overcome limitations posed by light-induced artifacts in combined optical-electrical neuroscience experiments.
Main Methods:
- Fabrication of transparent graphene microelectrodes with crack- and residue-free surfaces.
- Characterization of optical transmittance for deep tissue imaging.
- In vivo experimental validation of crosstalk-free integration with 2-photon microscopy and optogenetics.
Main Results:
- Achieved high optical transmittance through graphene electrodes for 2-photon imaging up to 1 mm deep.
- Demonstrated elimination of light-induced artifacts during combined optical and electrical recordings.
- Successfully integrated 2-photon microscopy, optogenetic stimulation, and cortical recordings in a single experiment.
Conclusions:
- Transparent graphene microelectrodes provide a viable solution for artifact-free integration of optical and electrical recording techniques.
- This technology facilitates investigation of neuronal activity across multiple spatial scales, from single neurons to populations.
- Enables more comprehensive in vivo studies by combining advanced optical methods with electrophysiology.
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