摘要
基于神经电极的神经电刺激和记录装置目前被广泛地应用于脑机接口和神经假体等领域。通过它们的研究能帮助人们更加深入地理解神经系统,并且能够使患有帕金森综合症、阿尔茨海默病症等神经系统缺陷的患者恢复一定的运动或感知能力。核磁兼容的神经电极在具有高空间分辨率的同时还可以获得核磁共振成像全脑功能状态分析,包括形态学结构分析、脑组织功能状况分析。然而,常用的贵金属神经电极如Pt-Ir电极,NiCr电极在磁共振下会产生伪影影响成像质量及磁场下热效应等生物安全性问题。我们制备了石墨烯包覆的铜基神经电极,通过电化学表征,体外神经细胞培养,活体免疫组化实验验证了其良好的生物相容性,核磁共振成像研究证明了其不会产生磁共振伪影,该电极可以记录到局部场电位和单个神经元的放电信号。
Magnetic resonance imaging(MRI) compatible neural electrodes are important for combining both high-resolution electrophysiological measurements with more global MRI mapping of brain activity critical for fundamental neuroscience studies as well as clinical evaluation and monitoring. Copper is a nearly ideal materials to use in MRI because it has magnetic susceptibility close to that of tissues. However, copper cannot be directly used as a implanted neural electrode because it exhibits cyto-and tissue toxicity. Here we overcome this key limitation by developing graphene encapsulated copper microwires, where the graphene is deposited directly on the copper surfaces. The toxicity of copper is largely eliminated, as evidenced by the electrochemistry measurement, in-vitro cell test, in-vivo histology studies, and MRI study.
引文
[1]Liu J,;Fu T M,;Cheng Z,;et al.Nature nanotechnology,2015,10(7):629-636.
[2]Xie C,;Liu J,;Fu T M,;et al.Nature materials,2015,14(12):1286-1292.