Department of Microsystems Engineering (IMTEK)-ElectroActive Coatings Group, University of Freiburg, Georges-Koehler-Allee 102, 79110 Freiburg, Germany.
BrainLinks-BrainTools Center, University of Freiburg, 79110 Freiburg, Germany.
ACS Appl Mater Interfaces. 2020 Apr 1;12(13):14855-14865. doi: 10.1021/acsami.9b22798. Epub 2020 Mar 20.
Bioelectronic devices, interfacing neural tissue for therapeutic, diagnostic, or rehabilitation purposes, rely on small electrode contacts in order to achieve highly sophisticated communication at the neural interface. Reliable recording and safe stimulation with small electrodes, however, are limited when conventional electrode metallizations are used, demanding the development of new materials to enable future progress within bioelectronics. In this study, we present a versatile process for the realization of nanostructured platinum (nanoPt) coatings with a high electrochemically active surface area, showing promising biocompatibility and providing low impedance, high charge injection capacity, and outstanding long-term stability both for recording and stimulation. The proposed electrochemical fabrication process offers exceptional control over the nanoPt deposition, allowing the realization of specific coating morphologies such as small grains, pyramids, or nanoflakes, and can moreover be scaled up to wafer level or batch fabrication under economic process conditions. The suitability of nanoPt as a coating for neural interfaces is here demonstrated, in vitro and in vivo, revealing superior stimulation performance under chronic conditions. Thus, nanoPt offers promising qualities as an advanced neural interface coating which moreover extends to the numerous application fields where a large (electro)chemically active surface area contributes to increased efficiency.
生物电子设备通过小的电极接触来实现治疗、诊断或康复目的，以达到神经界面的高度复杂的通信。然而，当使用传统的电极金属化时，可靠的记录和安全的刺激受到限制，这需要开发新材料以实现生物电子学的未来进展。在这项研究中，我们提出了一种通用的方法来实现具有高电化学活性表面积的纳米结构铂（nanoPt）涂层，该涂层具有良好的生物相容性，并提供低阻抗、高电荷注入能力和出色的长期稳定性，无论是在记录还是刺激方面。所提出的电化学制造工艺对 nanoPt 的沉积具有出色的控制能力，允许实现特定的涂层形态，如小颗粒、金字塔或纳米薄片，并且可以在经济的工艺条件下扩展到晶圆级或批量化制造。本文通过体外和体内实验证明了 nanoPt 作为神经接口涂层的适用性，揭示了其在慢性条件下优越的刺激性能。因此，nanoPt 作为一种先进的神经接口涂层具有很大的潜力，而且在许多需要大的（电）化学活性表面积来提高效率的应用领域也具有很大的潜力。
