Rustogi Paritosh, Judy Jack W
Electrical and Computer Engineering Department and the Nanoscience Institute for Medical and Engineering Technology, University of Florida, Gainesville, FL 32611 USA.
Electrical and Computer Engineering Department, Biomedical Engineering Department, Department of Neurology, and the Nanoscience Institute for Medical and Engineering Technology, University of Florida, Gainesville, FL 32611 USA.
J Microelectromech Syst. 2022 Jun;31(3):384-392. doi: 10.1109/jmems.2022.3159487. Epub 2022 Mar 22.
Demands for implantable bioelectronic devices to increase the number of channels for greater functional capacity and resolution, shrink implant size to minimize tissue response and patient burden, and support battery changes and electronics upgrades for long-term operational viability, cannot be met with existing implant-connector technology. In this paper we describe our novel approach to develop a rematable high-channel-density implant-connector technology, with a focus on the design, fabrication, and characterization of its microgasket. The microgaskets made of polydimethylsiloxane elastomer (PDMSe) have achieved much better electrical isolation for neural stimulation (~5 MΩ at 10 kHz) compared with conventional implant connectors (50 kΩ at 10 kHz), despite a 200-fold increase in channel density (conventional: ~0.0644 ch/mm, microgasket: ~12.8 ch/mm). The microgaskets also achieved high electrical isolation for neural recording (i.e., ~35 MΩ at 1 kHz) at the same high channel density. When mechanically compressed the microscale vias in the PDMSe microgaskets deform laterally, which could damage or enhance gasket-traversing conductive spring elements in each microscale via depending on their design. We have demonstrated that by lowering the height-to-width aspect ratio of the gasket vias, they can maintain their shape under clamping pressures high enough to achieve high isolation.
对于可植入生物电子设备的需求，如增加通道数量以提高功能容量和分辨率、缩小植入物尺寸以最小化组织反应和患者负担，以及支持电池更换和电子设备升级以实现长期运行可行性，现有的植入式连接器技术无法满足。在本文中，我们描述了一种开发可重新连接的高通道密度植入式连接器技术的新方法，重点是其微垫片的设计、制造和特性表征。由聚二甲基硅氧烷弹性体（PDMSe）制成的微垫片在神经刺激方面（10 kHz时约为5 MΩ）相比传统植入式连接器（10 kHz时为50 kΩ）实现了更好的电隔离，尽管通道密度提高了200倍（传统：约0.0644通道/毫米，微垫片：约12.8通道/毫米）。在相同的高通道密度下，微垫片在神经记录方面（即1 kHz时约为35 MΩ）也实现了高电隔离。当对PDMSe微垫片中的微尺度通孔进行机械压缩时，它们会横向变形，这可能会根据其设计损坏或增强每个微尺度通孔中穿过垫片的导电弹簧元件。我们已经证明，通过降低垫片通孔的高宽比，它们可以在足以实现高隔离的夹紧压力下保持其形状。
