神经刺激/记录fMEA的高性能3D结构铂纳米镀层的研究

High-Performance 3D Platinum Nanostructure Coating on fMEA for Stimulation/Recording

摘要:

为确保神经植入电极安全和长期有效的刺激/记录,柔性微电极阵列(fMEA)针对特定的植入环境,其设计和制造工艺应满足生物相容性、高分辨率、柔性和低阻抗等要求。 本文使用柔性基体聚酰亚胺提出了一种fMEA加工制造工艺方法,并探究了多种3D铂金属涂层结构在体外测试过程中性能的表现。与未修饰前的裸铂金属涂层表面相比较,3D微结构涂层在1kHz阻抗最大下降了94.77%,达到了0.824 kΩ,突破了1 kΩ的极限。而新颖的垒晶状结构涂层电极相比于其他形貌涂层电极的电荷存储容量(CSCc)提高程度最大可达6.67倍,达到13.47 mC cm_^-2。安全电荷注入能力相比较Pt-gray形貌的涂层电极高达19.6倍,达到了2.53 mC cm_^-2。因此,这种fMEA的加工制造方法将极大的提高神经刺激/记录过程中的分辨率和精准度,为生物医学植入器件的应用提供广阔的应用前景。

Abstract:

Flexible microelectrode array (fMEA) is one of the key devices for neural stimulation and recording. For its specific implantation environment, its design and manufacture should meet the requirements of biocompatibility, high resolution, flexibility and low impedance to ensure safe and long-term effective stimulation. In this paper, an fMEA fabrication process was proposed by using flexible polyimide matrix with a variety of 3D platinum nanostructure coatings were fabricated by electrochemical plating at 200 mm stimulation site. Compared with the surface of bare platinum coating, the impedance of 3D micro-structure coating decreased by 94.77% at 1 kHz, reaching 0.824 kΩ and breaking through the limit of 1 kΩ. Compared with other coated electrodes, the CSCc of the novel barrier crystal morphology coated electrodes can be increased by 6.67 times to 13.47 mC cm_^-2. The safe charge injection ability is 19.6 times higher than that of Pt-gray, reaching 2.53 mC cm_^-2. Therefore, this electroplating coating structure and process is promising for effective nerve stimulation/recording in various applications, and have broad application prospects in biomedical fields.