title: Transparent and flexible low noise graphene electrodes for simultaneous electrophysiology and neuroimaging.
abstract: Calcium imaging is a versatile experimental approach capable of resolving single neurons with single-cell spatial resolution in the brain. Electrophysiological recordings provide high temporal, but limited spatial resolution, because of the geometrical inaccessibility of the brain. An approach that integrates the advantages of both techniques could provide new insights into functions of neural circuits. Here, we report a transparent, flexible neural electrode technology based on graphene, which enables simultaneous optical imaging and electrophysiological recording. We demonstrate that hippocampal slices can be imaged through transparent graphene electrodes by both confocal and two-photon microscopy without causing any light-induced artefacts in the electrical recordings. Graphene electrodes record high-frequency bursting activity and slow synaptic potentials that are hard to resolve by multicellular calcium imaging. This transparent electrode technology may pave the way for high spatio-temporal resolution electro-optic mapping of the dynamic neuronal activity.
authors.affiliation: 1] Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Duygu
authors.initials: D
authors.lastname: Kuzum
authors.affiliation: 1] Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA [3] Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [4] Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Hajime
authors.initials: H
authors.lastname: Takano
authors.affiliation: 1] Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Euijae
authors.initials: E
authors.lastname: Shim
authors.affiliation: Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Jason C
authors.initials: JC
authors.lastname: Reed
authors.affiliation: Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Halvor
authors.initials: H
authors.lastname: Juul
authors.affiliation: 1] Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Richardson
authors.affiliation: 1] Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Julius
authors.initials: J
authors.lastname: de Vries
authors.affiliation: 1] Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Hank
authors.initials: H
authors.lastname: Bink
authors.affiliation: Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Marc A
authors.initials: MA
authors.lastname: Dichter
authors.affiliation: 1] Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Department of Neurosurgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Timothy H
authors.initials: TH
authors.lastname: Lucas
authors.affiliation: 1] Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA [3] Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [4] Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Douglas A
authors.initials: DA
authors.lastname: Coulter
authors.affiliation: 1] Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [3] Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Ertugrul
authors.initials: E
authors.lastname: Cubukcu
authors.affiliation: 1] Department of Bioengineering, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [2] Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA [3] Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
authors.forename: Brian
authors.initials: B
authors.lastname: Litt
mesh_terms: D000818:Animals; D016477:Artifacts; D001921:Brain / Q000378:metabolism / Q000473:pathology; D002118:Calcium / Q000378:metabolism; D004558:Electric Stimulation; D004562:Electrocardiography; D004566:Electrodes; D055724:Electrophysiological Phenomena; D004594:Electrophysiology / Q000379:methods; D005260:Female; D006108:Graphite / Q000737:chemistry; D006624:Hippocampus / Q000378:metabolism; D007091:Image Processing, Computer-Assisted; D007834:Lasers; D008297:Male; D051379:Mice; D018613:Microscopy, Confocal; D059906:Neuroimaging / Q000379:methods*; D009474:Neurons / Q000378:metabolism; D051381:Rats; D013059:Spectrum Analysis, Raman
chemical_list: D006108:Graphite; D002118:Calcium