【作者】 段小洁； 赵思源； 路林林； 付雪峰； 刘小军； 张永毅；

【Author】 Xiaojie Duan;Siyuan Zhao;Linlin Lu;Xuefeng Fu;Xiaojun Liu;Yongyi Zhang;Department of Biomedical Engineering, College of Engineering, Peking University;Suzhou Institute of Nano-Tech and Nano-Bionics (SINANO), Chinese Academy of Sciences;

【机构】 北京大学； 中国科学院苏州纳米技术与纳米仿生研究所；

【摘要】 神经信号难以长期稳定记录是制约神经网络研究和神经工程应用如脑机接口应用的主要因素之一,神经电极的柔性和小尺寸对减小由于大脑微运动带来的电极剪切力对大脑组织的损伤有很关键的作用,从而对提高植入电极的生物相容性,以及神经信号的长期稳定记录有重要的意义。本工作通过在电极的设计中使用碳纳米材料,制备了具有超高柔性的小尺寸神经电极,电极的柔性比传统电极有数量级的提高,尺寸也几乎有一个数量级的减小。利用此电极,我们实现了对神经元放电在数周内的连续稳定记录。组织学研究发现相对于同尺寸的传统非柔性电极,柔性碳电极周围无明显的神经元空缺区域和胶质细胞聚集,证实了柔性碳纳米电极的高生物相容性。另外,通过在金属电极材料表面包覆高质量石墨烯,大大消除了电极在生理条件下的腐蚀,以及对细胞和组织的毒性,提高了金属电极的生物相容性,从而为制备特殊功能的神经电极提供选择。更多还原

【Abstract】 Neural interfacing with electrodes is the basis of electrophysiological research and many therapeutic applications such as brain-computer interface. Conventional electrodes have limitations in terms of chronic deterioration of the probe-tissue interfaces, which have been attributed to factors such as size and mechanical mismatch between the implants and the brain tissue. Here, we overcome these challenge by fabricating neural electrodes that combine small size and high flexibility using low-dimensional carbon materials. These highly flexible electrodes were used to record single-unit action potentials and local field potentials from rat hippocampus. Significantly, histology studies show that these electrodes exhibit high biocompatibility as evidenced by the close proximity of neurons to the electrodes. Furthermore, we encapsulated metal electrodes with high-quality graphene, which act as an effective corrosion barrier to eliminate the toxicity of the metal to cells and tissues. This graphene encapsulated metal electrode is critical for the fabrication and application of neural electrodes with multi-modality functions.更多还原