Massey Travis L, Gleick Jeremy R, Haque Razi-Ul M
Materials Engineering Division, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.
IEEE Biomed Circuits Syst Conf. 2021 Oct;2021. doi: 10.1109/biocas49922.2021.9644948. Epub 2021 Dec 23.
Neural interfaces with increasing channel counts require a scalable means of testing. While multiplexed potentiostats have long been the solution to this problem, most have been dedicated to one specific probe design or potentiostat, limited in the electrochemical techniques available, inordinately expensive, or they support multiplexing of too few channels. We present the design of an automated multiplexed potentiostat system that addresses these limitations-it is easily generalizable to any probe and potentiostat, supports any electrochemical technique available with the potentiostat, is low-cost, and can readily be expanded to hundreds of channels with support for multiple simultaneous potentiostats. This paper discusses the design philosophy and architecture of our 512-channel, 4-potentiostat system before demonstrating functionality with electrochemical impedance spectroscopy data, cyclic voltammetry curves, and an example of electrochemical surface modification, all on functional implantable microelectrode arrays currently being used for electrophysiological studies. Finally, we discuss the limitations to some sensitive or high-frequency impedance measurements due to reactive parasitics.
通道数不断增加的神经接口需要一种可扩展的测试方法。虽然多路复用恒电位仪长期以来一直是解决这个问题的方法，但大多数都专用于一种特定的探头设计或恒电位仪，在可用的电化学技术方面受到限制，价格过高，或者支持的通道多路复用数量太少。我们提出了一种自动化多路复用恒电位仪系统的设计，该系统解决了这些限制——它很容易推广到任何探头和恒电位仪，支持恒电位仪可用的任何电化学技术，成本低，并且可以通过支持多个同时使用的恒电位仪轻松扩展到数百个通道。本文在展示电化学阻抗谱数据、循环伏安曲线以及电化学表面改性示例的功能之前，讨论了我们的512通道、4恒电位仪系统的设计理念和架构，所有这些都是在目前用于电生理研究的功能性植入式微电极阵列上进行的。最后，我们讨论了由于电抗寄生效应导致的一些敏感或高频阻抗测量的局限性。
