An exceptionally conductive hydrogel for all-organic, ultraflexible, and chronic neural interfaces
Abstract
Chronic neural interfaces are essential for advancing brain–computer interfaces, neuroprosthetics, and neuromodulation technologies. However, a long-standing trade-off between performance and longevity persists due to the scarcity of materials that simultaneously achieve superior electrical performance, mechanical compliance, and biocompatibility. Here, we overcome this limitation with an all-organic, ultraflexible electrocorticography (ECoG) design that features a thickness of only 9 µm, achieving low electrode–tissue impedance and durability in vivo. Central to this design is a conductive hydrogel featuring an interfacial percolation (CHIP) microstructure, with tunable hydration levels and softness, achieving a highest in-plane electrical conductivity of 2,512 S cm –1 . We further developed an in-plane swelling control with a dry, soft-protective etching strategy that preserves the structural integrity during hydrogel processing. The resulting all-organic ECoG array conforms to the cortical surface, minimizing foreign body response and providing exceptional signal quality, with the longest record up to 550 d.
Article Details
Journal Info
Proceedings of the National Academy of Sciences
National Academy of Sciences
Authors (14)
Ruiqi Zhu
State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), Frontier Interdisciplinary Science Research Center, School of Chemistry and Chemical Engineering
Zhengwei Hu
Chinese Academy of Sciences Key Laboratory of Brain Connectome and Manipulation, the Brain Cognition and Brain disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions
Zirui Lou
Institute of Materials Research, Shenzhen International Graduate School, Tsinghua University
Fei Xie
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian 116023, China
Shuainan Zhao
Chinese Academy of Sciences Key Laboratory of Brain Connectome and Manipulation, Shenzhen-Hong Kong Institute of Brain Science, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences
Xuechen Jiao
National Synchrotron Radiation Laboratory
Jianyu Wang
Kenjiro Fukuda
Thin-Film Device Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
Xiaodong Chen
Innovative Centre for Flexible Devices (iFLEX), Max Planck-NTU Joint Lab for Artificial Senses, School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Republic of Singapore
Wenping Hu
Hui-Ming Cheng
Institute of Technology for Carbon Neutrality, Shenzhen Key Laboratory of Energy Materials for Carbon Neutrality, Shenzhen Institutes of Advanced Technology
Xiaojian Li
Anhui Province Key Laboratory for Control and Applications of Optoelectronic Information Materials
Takao Someya
Thin-Film Device Laboratory, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
Xiaomin Xu
Curtin Centre for Advanced Energy Materials and Technologies (CAEMT), Western Australian School of Mines (WASM)