State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai, China.
Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA.
Biomed Microdevices. 2020 Jun 6;22(3):43. doi: 10.1007/s10544-020-00498-0.
This paper presents a fabrication method for glassy carbon neural electrode arrays that combines 3D printing and chemical pyrolysis technology. The carbon electrodes have excellent biological compatibility and can be used in neural signal recording. A pretreated Si wafer is used as the substrate for 3D printing, and then, stereolithography 3D printing technology is employed to print photosensitive resin into a cone shape. Next, chemical pyrolysis is applied to convert the 3D prints into glassy carbon electrodes and modify the electrochemical performance of the carbon electrodes. Finally, the glassy carbon electrodes are packed with conductive wires and PDMS. The proposed fabrication method simplifies the manufacturing process of carbon materials, and electrodes can be fabricated without the need of deep reactive ion etching (DRIE). The height of the carbon electrodes is 1.5 mm, and the exposure area of the tips is 0.78 mm, which is convenient for the implantation procedure. The specific capacitance of the glassy carbon arrays is higher than that of a platinum electrode (9.18 mF/cm vs 3.32 mF/cm, respectively), and the impedance at 1 kHz is lower (7.1 kΩ vs 8.8 kΩ). The carbon electrodes were tested in vivo, and they showed excellent performance in neural signal recording. The signal-to-noise ratio of the carbon electrodes is 50.73 ± 6.11, which is higher than that of the Pt electrode (20.15 ± 5.32) under the same testing conditions. The proposed fabrication method of glassy carbon electrodes provides a novel approach to manufacture penetrating electrodes for nerve interfaces in biomedical engineering and microelectromechanical systems.
本文提出了一种结合 3D 打印和化学热解技术的玻璃碳神经电极阵列制造方法。碳电极具有优异的生物相容性，可用于神经信号记录。预处理后的 Si 片用作 3D 打印的基底，然后使用立体光刻 3D 打印技术将光敏树脂打印成锥形。接下来，进行化学热解将 3D 打印件转化为玻璃碳电极，并修饰碳电极的电化学性能。最后，将玻璃碳电极用导电丝和 PDMS 封装。所提出的制造方法简化了碳材料的制造工艺，并且无需深反应离子刻蚀（DRIE）即可制造电极。碳电极的高度为 1.5mm，尖端的暴露面积为 0.78mm，便于植入程序。玻璃碳阵列的比电容高于铂电极（分别为 9.18 mF/cm 和 3.32 mF/cm），在 1kHz 时的阻抗更低（分别为 7.1 kΩ 和 8.8 kΩ）。碳电极在体内进行了测试，在神经信号记录方面表现出优异的性能。在相同的测试条件下，碳电极的信噪比为 50.73±6.11，高于铂电极（20.15±5.32）。所提出的玻璃碳电极制造方法为生物医学工程和微机电系统中的神经接口制造穿透电极提供了一种新方法。
