KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea.
School of Electrical Engineering, Kookmin University, Seoul 02707, Republic of Korea.
Biosens Bioelectron. 2018 Oct 15;117:436-443. doi: 10.1016/j.bios.2018.06.035. Epub 2018 Jun 20.
In this paper, we present the design, fabrication, and performance evaluation of a polyimide-based flexible neural probe for the precise site stimulation and recording in the deep brain. The probe consists of five electrodes: one for stimulation, another for ground and the other three for recording electrodes. This probe is designed to be foldable, enabling easy insertion into the deep brain via temporary tungsten guide sticks. Because of its small cross-sectional area and the flexibility of the polyimide, the probe causes minimum damage to the neural tissue and does not show any evidence of serious immune reactions such as high density of macrophage or microglia. Around the simulation electrodes, an additional ground electrode prevents the stimulation of the undesired sites in the brain. To ensure we stimulate the target point specifically, for instance STh in this study, we confirm through both finite element analyses and in vitro tests. With the additional ground electrodes, we observe the leakage power decreased by about 80%. To check the performance of the probe, we demonstrate animal experiments using rats, and neural spike signals from STh in the 7-mm deep brain are successfully recorded after implantation.
本文提出了一种基于聚酰亚胺的柔性神经探针的设计、制作和性能评估，用于在深部脑内进行精确的位点刺激和记录。该探针由五个电极组成：一个用于刺激，另一个用于接地，另外三个用于记录电极。该探针设计为可折叠式，通过临时钨制引导棒可轻松插入深部脑内。由于其小的横截面积和聚酰亚胺的柔韧性，探针对神经组织的损伤最小，并且没有显示出任何严重免疫反应的证据，如高密度的巨噬细胞或小胶质细胞。在模拟电极周围，增加一个接地电极可以防止大脑中不需要的部位受到刺激。为了确保我们能够特异性地刺激目标点，例如本研究中的 STh，我们通过有限元分析和体外测试进行了验证。通过增加接地电极，我们观察到泄漏功率降低了约 80%。为了检查探针的性能，我们使用大鼠进行了动物实验，在植入后成功记录了来自 7 毫米深部脑内的 STh 的神经尖峰信号。
