Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA.
IEEE Trans Biomed Eng. 2010 Oct;57(10):2485-94. doi: 10.1109/TBME.2010.2052617. Epub 2010 Jun 14.
A method for fabricating polydimethylsiloxane (PDMS) based microelectrode arrays (MEAs) featuring novel conical-well microelectrodes is described. The fabrication technique is reliable and efficient, and facilitates controllability over both the depth and the slope of the conical wells. Because of the high-PDMS elasticity (as compared to other MEA substrate materials), this type of compliant MEA is promising for acute and chronic implantation in applications that benefit from conformable device contact with biological tissue surfaces and from minimal tissue damage. The primary advantage of the conical-well microelectrodes--when compared to planar electrodes--is that they provide an improved contact on tissue surface, which potentially provides isolation of the electrode microenvironment for better electrical interfacing. The raised wells increase the uniformity of current density distributions at both the electrode and tissue surfaces, and they also protect the electrode material from mechanical damage (e.g., from rubbing against the tissue). Using this technique, electrodes have been fabricated with diameters as small as 10 μm and arrays have been fabricated with center-to-center electrode spacings of 60 μm. Experimental results are presented, describing electrode-profile characterization, electrode-impedance measurement, and MEA-performance evaluation on fiber bundle recruitment in spinal cord white matter.
一种基于聚二甲基硅氧烷（PDMS）的微电极阵列（MEA）的制造方法，其特点是具有新颖的锥形井微电极。该制造技术可靠且高效，可控制锥形井的深度和斜率。由于 PDMS 的高弹性（与其他 MEA 衬底材料相比），这种顺应性 MEA 有望在急性和慢性植入应用中得到应用，这些应用受益于与生物组织表面的顺应性设备接触和最小的组织损伤。与平面电极相比，锥形井微电极的主要优势在于它们在组织表面提供了更好的接触，这可能为电极微环境提供了更好的电接口隔离。凸起的井增加了电极和组织表面的电流密度分布的均匀性，并且还保护电极材料免受机械损伤（例如，免受与组织的摩擦）。使用这种技术，可以制造直径小至 10 μm 的电极，并且可以制造中心到中心电极间距为 60 μm 的电极阵列。本文介绍了电极轮廓特性、电极阻抗测量以及在脊髓白质纤维束募集方面的 MEA 性能评估的实验结果。
