Electrostatic microactuators for precise positioning of neural microelectrodes
Electrostatic microactuators for precise positioning of neural microelectrodes
复制标题
DOI：
10.1109/tbme.2005.855712
复制
发表时间：
2005-10-01
影响因子：
4.6
通讯作者：
Gilletti, A
中科院分区：
文献类型：
--
作者：
Muthuswamy, J;Okandan, M;Gilletti, A
用于监测单个和多个神经元动作电位的微电极阵列往往不能在一段时间内记录同一群神经元，这可能是由于神经元远离微电极的微运动，记录部位周围的胶质细胞增生以及由于行为引起的大脑运动。我们在这里报告了一种新型静电微致动微电极，它将使微电极在脑组织内精确重新定位。静电梳状驱动微致动器和相关的微电极是使用SUMMiT V(TM) （Sandia的超平面多层MEMS技术）工艺制造的，这是Sandia国家实验室的五层多晶硅微加工技术。微加工微执行器；微致动器允许微电极在任何方向上进行高达5毫米的线性平移，使其适用于定位啮齿动物大脑深层结构中的微电极。在用环氧树脂对微电极进行绝缘后，整体平移量减少到约2毫米，用于监测多单元活性。各层;能够以几个微牛顿量级的力驱动脑组织中的微电极。在急性实验中，从成年大鼠的体感觉皮层获得了单单元记录，证明了该技术的可行性。在这项技术能够在长期实验中得到验证之前，需要进一步优化绝缘、封装和互连问题。
Microelectrode arrays used for monitoring single and multineuronal action potentials often fail to record from the same population of neurons over a period of time likely due to micro-motion of neurons away from the microelectrode, gliosis around the recording site and also brain movement due to behavior. We report here novel electrostatic microactuated microelectrodes that will enable precise repositioning of the microelectrodes within the brain tissue. Electrostatic comb-drive microactuators and associated microelectrodes are fabricated using the SUMMiT V(TM) (Sandia's Ultraplanar Multilevel MEMS Technology) process, a five-layer polysilicon micromachining technology of the Sandia National labs, NM. The microfabricated microactuators; enable precise bidirectional positioning of the microelectrodes in the brain with accuracy in the order of 1 mu m. The microactuators allow for a linear translation of the microelectrodes of up to 5 mm in either direction making it suitable for positioning microelectrodes in deep structures of a rodent brain. The overall translation was reduced to approximately 2 mm after insulation of the microelectrodes with epoxy for monitoring multiunit activity. The microactuators; are capable of driving the microelectrodes in the brain tissue with forces in the order of several micro-Newtons. Single unit recordings were obtained from the somatosensory cortex of adult rats in acute experiments demonstrating the feasibility of this technology. Further optimization of the insulation, packaging and interconnect issues will be necessary before this technology can be validated in long-term experiments.