Keohan Frank, Wei Xuefeng F, Wongsarnpigoon Amorn, Lazaro Edgar, Darga John E, Grill Warren M
Cape Cod Research, Inc. East Falmouth, MA, USA.
J Biomater Sci Polym Ed. 2007;18(8):1057-73. doi: 10.1163/156856207781494395.
This study explored the feasibility of applying nanocomposites derived from conducting organic polymers and silicone elastomers to fabricate electrodes for neural stimulation. A novel combination of nanoparticulate polypyrrole polymerized within a processable elastomeric silicone host polymer was evaluated in vitro and in vivo. The electrical properties of the elastomeric conductors were strongly dependent on their composition, and mixtures were identified that provided high and stable conductivity. Methods were developed for incorporating conductive polymer-siloxane co-polymer nanocomposite and silicone insulating polymers into thin-layered structures for simple single-poled electrode fabrication. In vitro testing revealed that the materials were stable under continuous pulsing for at least 10 days. Single contact prototype nerve cuff electrodes were fabricated and device functionality was demonstrated in vivo following acute implantation. The results of this study demonstrate the feasibility of conductive elastomers for peripheral nerve stimulating electrodes. Matching the mechanical properties of cuff electrode to those of the underlying neural tissue is expected to improve the long-term tissue response to the presence of the electrode.
本研究探讨了应用由导电有机聚合物和硅橡胶制成的纳米复合材料来制造神经刺激电极的可行性。对在可加工的弹性体硅橡胶主体聚合物中聚合的纳米颗粒聚吡咯的一种新型组合进行了体外和体内评估。弹性体导体的电学性质强烈依赖于其组成，并且确定了具有高且稳定导电性的混合物。开发了将导电聚合物 - 硅氧烷共聚物纳米复合材料和硅橡胶绝缘聚合物纳入薄层结构以制造简单单极电极的方法。体外测试表明，这些材料在连续脉冲下至少10天保持稳定。制造了单触点原型神经袖套电极，并在急性植入后在体内证明了装置的功能。本研究结果证明了导电弹性体用于外周神经刺激电极的可行性。预计使袖套电极的机械性能与下面的神经组织的机械性能相匹配将改善组织对电极存在的长期反应。
