Flexible, diamond-based microelectrodes fabricated using the diamond growth side for neural sensing  

作　　者：Bin Fan Cory A.Rusinek Cort H.Thompson Monica Setien Yue Guo Robert Rechenberg Yan Gong Arthur J.Weber Michael F.Becker Erin Purcell Wen Li 

机构地区：[1]Department of Electrical and Computer Engineering,Michigan State University,East Lansing,MI,USA [2]Fraunhofer USA Center for Coatings and Diamond Technologies,East Lansing,MI,USA [3]Department of Biomedical Engineering,Michigan State University,East Lansing,MI,USA [4]Department of Physiology,Michigan State University,East Lansing,MI,USA

出　　处：《Microsystems & Nanoengineering》2020年第1期742-753,共12页微系统与纳米工程（英文）

基　　金：This work was supported in part by the National Institutes of Health(NIH R21NS096637-02)and the Michigan State University-Fraunhofer USA,Inc.Center for Coatings and Diamond Technologies;E.P.,C.H.T.,and M.S.were partially supported by NIH/NINDS(1R01NS10745101A1)and the Departments of Biomedical Engineering and Electrical and Computer Engineering at Michigan State University.

摘　　要：Diamond possesses many favorable properties for biochemical sensors,including biocompatibility,chemical inertness,resistance to biofouling,an extremely wide potential window,and low double-layer capacitance.The hardness of diamond,however,has hindered its applications in neural implants due to the mechanical property mismatch between diamond and soft nervous tissues.Here,we present a flexible,diamond-based microelectrode probe consisting of multichannel boron-doped polycrystalline diamond(BDD)microelectrodes on a soft Parylene C substrate.We developed and optimized a wafer-scale fabrication approach that allows the use of the growth side of the BDD thin film as the sensing surface.Compared to the nucleation surface,the BDD growth side exhibited a rougher morphology,a higher sp^(3) content,a wider water potential window,and a lower background current.The dopamine(DA)sensing capability of the BDD growth surface electrodes was validated in a 1.0 mM DA solution,which shows better sensitivity and stability than the BDD nucleation surface electrodes.The results of these comparative studies suggest that using the BDD growth surface for making implantable microelectrodes has significant advantages in terms of the sensitivity,selectivity,and stability of a neural implant.Furthermore,we validated the functionality of the BDD growth side electrodes for neural recordings both in vitro and in vivo.The biocompatibility of the microcrystalline diamond film was also assessed in vitro using rat cortical neuron cultures.

关 键 词：NEURAL FILM DIAMOND 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] TM91[自动化与计算机技术—控制科学与工程]