To understand the complex dynamics of neural activity in the brain across various temporal and spatial scales,it is crucial to record intracortical multimodal neural activity by combining electrophysiological recordin...To understand the complex dynamics of neural activity in the brain across various temporal and spatial scales,it is crucial to record intracortical multimodal neural activity by combining electrophysiological recording and calcium imaging techniques.This poses significant constraints on the geometrical,mechanical,and optical properties of the electrodes.Here,transparent flexible graphene–ITO-based neural microelectrodes with small feature sizes are developed and validated for simultaneous electrophysiology recording and calcium imaging in the hippocampus of freely moving mice.A micro-etching technique and an oxygen plasma pre-treating method are introduced to facilitate large-area graphene transfer and establish stable low-impedance contacts between graphene and metals,leading to the batch production of high-quality microelectrodes with interconnect widths of 10μm and recording sites diameters of 20μm.These electrodes exhibit appropriate impedance and sufficient transparency in the field of view,enabling simultaneous recording of intracortical local field potentials and even action potentials along with calcium imaging in freely moving mice.Both types of electrophysiological signals are found to correlate with calcium activity.This proof-of-concept work demonstrates that transparent flexible graphene–ITO-based neural microelectrodes are promising tools for multimodal neuroscience research.展开更多
The paper is aimed to investigate the adhesion and growth of neural cells on different microelectrode surfaces and their possible mechanism, thereby an optimum interfacial material or substrate for neural microelectro...The paper is aimed to investigate the adhesion and growth of neural cells on different microelectrode surfaces and their possible mechanism, thereby an optimum interfacial material or substrate for neural microelectrode can be chosen. Three different materials including platinum, gold, and pyrolyzed photoresist derived carbon material, in the forms of plasma-treated and non-treated ones, were tested. Surface properties of the microelectrodes in terms of surface morphology and wettability were examined; then their biocompatibility was tested by co-culturing with SK-N-SH neuroblastoma cells. Results of experiments demonstrated that, compared with platinum and gold, carbon could be a better substrate for cell adhesion and growth,especially for the plasma-treated carbon surface. The high wetting property of plasma-treated carbon accounted for the preferable adhesion of cell on its surface. Therefore, plasma-treated carbon can potentially be employed for fabrication of biocompatible and stable neural electrodes, which is beneficial for neural engineering research, such as regeneration from injury or disease therapy of neural system.展开更多
Extracellular matrix(ECM)-based implantable neural electrodes(NEs)were achieved using a microfabrication strategy on naturalsubstrate-based organic materials.The ECM-based design minimized the introduction of non-natu...Extracellular matrix(ECM)-based implantable neural electrodes(NEs)were achieved using a microfabrication strategy on naturalsubstrate-based organic materials.The ECM-based design minimized the introduction of non-natural products into the brain.Further,it rendered the implants sufficiently rigid for penetration into the target brain region and allowed them subsequently to soften to match the elastic modulus of brain tissue upon exposure to physiological conditions,thereby reducing inflammatory strain fields in the tissue.Preliminary studies suggested that ECM-NEs produce a reduced inflammatory response compared with inorganic rigid and flexible approaches.In vivo intracortical recordings from the rat motor cortex illustrate one mode of use for these ECM-NEs.展开更多
基金support of the National Key R&D Program of China(2022YFF1202303 and 2023YFF1203702)NSFC-Guangdong Joint Fund(U20A6005)+2 种基金the National Natural Science Foundation of China(62071447)STI2030-Major Projects(2021ZD0200100)the Science and Technology Innovation Committee of Shenzhen Municipality(JCYJ20220818101611024).
文摘To understand the complex dynamics of neural activity in the brain across various temporal and spatial scales,it is crucial to record intracortical multimodal neural activity by combining electrophysiological recording and calcium imaging techniques.This poses significant constraints on the geometrical,mechanical,and optical properties of the electrodes.Here,transparent flexible graphene–ITO-based neural microelectrodes with small feature sizes are developed and validated for simultaneous electrophysiology recording and calcium imaging in the hippocampus of freely moving mice.A micro-etching technique and an oxygen plasma pre-treating method are introduced to facilitate large-area graphene transfer and establish stable low-impedance contacts between graphene and metals,leading to the batch production of high-quality microelectrodes with interconnect widths of 10μm and recording sites diameters of 20μm.These electrodes exhibit appropriate impedance and sufficient transparency in the field of view,enabling simultaneous recording of intracortical local field potentials and even action potentials along with calcium imaging in freely moving mice.Both types of electrophysiological signals are found to correlate with calcium activity.This proof-of-concept work demonstrates that transparent flexible graphene–ITO-based neural microelectrodes are promising tools for multimodal neuroscience research.
基金National Basic Research Program of China (973 Program) (No.2011CB707505)National Natural Science Foundations of China(No.30872629,30900315,60906055)National High-Tech R & D Program of China (863 Program) (No.2009AA04Z326)
文摘The paper is aimed to investigate the adhesion and growth of neural cells on different microelectrode surfaces and their possible mechanism, thereby an optimum interfacial material or substrate for neural microelectrode can be chosen. Three different materials including platinum, gold, and pyrolyzed photoresist derived carbon material, in the forms of plasma-treated and non-treated ones, were tested. Surface properties of the microelectrodes in terms of surface morphology and wettability were examined; then their biocompatibility was tested by co-culturing with SK-N-SH neuroblastoma cells. Results of experiments demonstrated that, compared with platinum and gold, carbon could be a better substrate for cell adhesion and growth,especially for the plasma-treated carbon surface. The high wetting property of plasma-treated carbon accounted for the preferable adhesion of cell on its surface. Therefore, plasma-treated carbon can potentially be employed for fabrication of biocompatible and stable neural electrodes, which is beneficial for neural engineering research, such as regeneration from injury or disease therapy of neural system.
基金This work was funded by the Defense Advanced Research Projects Agency(DARPA)MTO under the auspices of Dr.Jack Judy through the Space and Naval Warfare Systems Center,Pacific Grant/Contract No.N66001-11-1-4014.
文摘Extracellular matrix(ECM)-based implantable neural electrodes(NEs)were achieved using a microfabrication strategy on naturalsubstrate-based organic materials.The ECM-based design minimized the introduction of non-natural products into the brain.Further,it rendered the implants sufficiently rigid for penetration into the target brain region and allowed them subsequently to soften to match the elastic modulus of brain tissue upon exposure to physiological conditions,thereby reducing inflammatory strain fields in the tissue.Preliminary studies suggested that ECM-NEs produce a reduced inflammatory response compared with inorganic rigid and flexible approaches.In vivo intracortical recordings from the rat motor cortex illustrate one mode of use for these ECM-NEs.
