基于正交试验方法的柔性神经电极优化设计

doi:10.16183/j.cnki.jsjtu.2019.068

摘要/Abstract

摘要：

对柔性神经电极进行优化设计,综合弹性模量、电极厚度、楔形角这3个参数进行研究,利用正交试验设计的思想设置试验组,采用ANSYS软件研究不同试验组的脑组织最大应变,并根据试验结果提出组合式柔性神经电极的设计思路.研究结果表明,在弹性模量为8.5GPa、电极厚度为15μm、楔形角为45° 的情况下,微动造成的脑组织最大应变最小,为 5.5627×10^-2.一种中间层聚合物弹性模量为5.5GPa,两边层聚合物弹性模量为8.5GPa的三明治结构的组合式柔性电极,在微动损伤以及植入形变上均具有一定的优势.

关键词: 柔性电极, 有限元, 正交试验, 优化设计

Abstract:

In order to optimize the design of flexible neural electrodes, three parameters of elastic modulus, electrode thickness, and wedge angle are comprehensively studied. The experimental groups are established based on orthogonal experimental design. The maximum strain of brain tissue in different experimental groups are evaluated by ANSYS. In addition, a new hybrid flexible electrode is designed based on the stimulation results. The experimental results reveal that when elastic modulus is 8.5GPa, thickness is 15μm and wedge angle is 45°, the maximum strain of brain tissue due to micromotion is the smallest, i.e., 5.5627×10^-2. Moreover, a sandwich-type hybrid flexible neural electrode is designed with an elastic modulus of 8.5GPa on both sides and an elastic modulus of 5.5GPa in the intermediate layer. The sandwich-type structure can effectively reduce micromotion damage and implant deformation compared to the traditional electrode.

Key words: flexible electrode, finite element, orthogonal experiment, optimized design

中图分类号:

R318.01
Q66

谢颉, 张文光, 尹雪乐, 李伟. 基于正交试验方法的柔性神经电极优化设计[J]. 上海交通大学学报, 2020, 54(8): 785-791.

XIE Jie, ZHANG Wenguang, YIN Xuele, LI Wei. Optimization Design of Flexible Neural Electrodes Based on Orthogonal Experimental Method[J]. Journal of Shanghai Jiaotong University, 2020, 54(8): 785-791.

图/表 12

图1

表1

图2

表2

表3

图3

图4

表4

表5

图5

图6

表6

参考文献 17

[1]	PERLMUTTER J S, MINK J W. Deep brain stimulation[J]. Annual Review of Neuroscience, 2006,29(1):229-257. doi: 10.1146/annurev.neuro.29.051605.112824 URL
[2]	ETHIER C, OBY E R, BAUMAN M J, et al. Restoration of grasp following paralysis through brain-controlled stimulation of muscles[J]. Nature, 2012,485(7398):368-371. doi: 10.1038/nature10987 URL
[3]	RUTHER P, HERWIK S, KISBAN S, et al. Recent progress in neural probes using silicon MEMS technology[J]. IEEJ Transactions on Electrical and Electronic Engineering, 2010,5(5):505-515. doi: 10.1002/tee.20566 URL
[4]	PATIL A C, THAKOR N V. Implantable neurotechnologies: A review of micro- and nanoelectrodes for neural recording[J]. Medical & Biological Engineering & Computing, 2016,54(1):23-44. doi: 10.1016/0002-9343(73)90079-X URL
[5]	SEYMOUR J P, KIPKE D R. Neural probe design for reduced tissue encapsulation in CNS[J]. Biomaterials, 2007,28(25):3594-3607. doi: 10.1016/j.biomaterials.2007.03.024 URL
[6]	曹张玉, 石云波, 徐胜. 植入式柔性神经刺激微电极研究进展[J]. 传感器与微系统, 2015,34(2):1-4.
	CAO Zhangyu, SHI Yunbo, XU Sheng. Research progress of implantable flexible neural stimulating microelectrode[J]. Transducer and Microsystem Technologies, 2015,34(2):1-4.
[7]	BARZ F, RUTHER P, TAKEUCHI S, et al. Mechanically adaptive silicon-based neural probes for chronic high-resolution neural recording[J]. Procedia Engineering, 2015,120:952-955. doi: 10.1016/j.proeng.2015.08.816 URL
[8]	KIM E G R, JOHN J K, TU H, et al. A hybrid silicon-parylene neural probe with locally flexible regions[J]. Sensors and Actuators B: Chemical, 2014,195:416-422. doi: 10.1016/j.snb.2014.01.048 URL
[9]	马亚坤, 张文光, 李正伟. 基于神经电极形状参数的脑组织微动损伤仿真[J]. 上海交通大学学报, 2015,49(12):1882-1887.
	MA Yakun, ZHANG Wenguang, LI Zhengwei. Simulation of brain micromotion induced injury based on investigation of neural probe geometry parameters[J]. Journal of Shanghai Jiao Tong University, 2015,49(12):1882-1887.
[10]	徐仲安, 王天保, 李常英, 等. 正交试验设计法简介[J]. 科技情报开发与经济, 2002(5):148-150.
	XU Zhong’an, WANG Tianbao, LI Changying, et al. Brief introduction to the orthogonal test design[J]. Sci/Tech Information Development & Economy, 2002(5):148-150.
[11]	HAMZAVI N, TSANG W M, SHIM V P W. Nonlinear elastic brain tissue model for neural probe-tissue mechanical interaction[C]// 2013 6th International IEEE/EMBS Conference on Neural Engineering. San Diego, CA, USA: IEEE, 2013: 14001713.
[12]	RASHID B, DESTRADE M, GILCHRIST M D. Hyperelastic and viscoelastic properties of brain tissue in tension[C]// ASME 2012 International Mechanical Engineering Congress and Exposition. Houston, Texas, USA: ASME, 2012: 921-929.
[13]	吴栋栋, 张文光, MERCERON G, 等. 神经电极-脑组织界面微动环境力学特性仿真[J]. 浙江大学学报(工学版), 2013,47(2):256-260.
	WU Dongdong, ZHANG Wenguang, MERCERON Gilles, et al. Mechanical simulation of neural electrode-brain tissue interface under different micro-motion conditions[J]. Journal of Zhejiang University (Engineering Science), 2013,47(2):256-260.
[14]	GILLETTI A, MUTHUSWAMY J. Brain micromotion around implants in the rodent somatosensory cortex[J]. Journal of Neural Engineering, 2006,3(3):189-195. doi: 10.1088/1741-2560/3/3/001 URL
[15]	XUE N, WANG D H, LIU C X, et al. A biodegradable porous silicon and polymeric hybrid probe for electrical neural signal recording[J]. Sensors and Actuators B: Chemical, 2018,272:314-323. doi: 10.1016/j.snb.2018.06.001 URL
[16]	LECOMTE A, DESCAMPS E, BERGAUD C. A review on mechanical considerations for chronically-implanted neural probes[J]. Journal of Neural Engineering, 2018,15(3):031001. doi: 10.1088/1741-2552/aa8b4f URL
[17]	POLANCO M, BAWAB S, YOON H. Computational assessment of neural probe and brain tissue interface under transient motion[J]. Biosensors, 2016,6(2):27. doi: 10.3390/bios6020027 URL

参数	取值
ρ/(g·cm^-3)	1.0425
μ/Pa	5160
k	6.95
G₁	0.5837
G₂	0.2387
τ₁/s	0.02571
τ₂/s	0.02570

试验序号	试验参数			试验方案
试验序号	E_i	h_i	α_i	试验方案
1	E₁	h₁	α₁	E₁h₁α₁
2	E₁	h₂	α₂	E₁h₂α₂
3	E₁	h₃	α₃	E₁h₃α₃
4	E₂	h₂	α₃	E₂h₂α₃
5	E₂	h₃	α₁	E₂h₃α₁
6	E₂	h₁	α₂	E₂h₁α₂
7	E₃	h₃	α₂	E₃h₃α₂
8	E₃	h₁	α₃	E₃h₁α₃
9	E₃	h₂	α₁	E₃h₂α₁

试验序号	E_i/GPa	h_i/μm	α_i/(°)	ε_i×10²
14	5.5-8.5-5.5	15	45	5.4063
15	8.5-5.5-8.5	15	45	3.8834