Bui Cat-Vu H, Maliakal Neethu, Ulusan Hasan, Hierlemann Andreas, Cardes Fernando
Bio Engineering Laboratory, Department of Biosystems Science and Engineering, ETH Zurich, 4056 Basel, Switzerland.
Department of Electrical and Electronics Engineering, Middle East Technical University, 06800 Ankara, Türkiye.
Sensors (Basel). 2025 May 2;25(9):2874. doi: 10.3390/s25092874.
Electrode designs and materials have become an increasingly important performance driver for microelectrode arrays, which are among the essential tools for cellular electrophysiology. Ongoing works have continuously innovated over a diverse range of electrode shapes, sizes, and materials. The large design and fabrication parameter space represents rich opportunities for optimizing performance and functionalities as well as a challenge for electrode developers due to a lack of predictive simulation software to aid design works. Electrode prototypes often need to be fabricated, empirically evaluated, and iteratively optimized at significant cost. Efficient hardware testing solutions to aid the development of new electrodes, especially at an early stage when the number of candidate designs is still high, are therefore increasingly important. Here, we propose and implement a cost-effective testbed platform, which is aimed at obtaining first-order characteristics from electrode prototypes to inform early-stage screening and refinement. Upon testing with microfabricated electrodes, the platform was shown to achieve an impedance measurement accuracy comparable to commercial equipment and effectively recorded extracellular action potentials of in vitro rat cortical neurons. By providing relevant electrode testing at a significantly lower cost, in a more compact form, and with greater ease of assembly, compared to existing hardware solutions, the presented testbed can meaningfully lower entry barriers for the development of new array-based electrophysiological microelectrodes.
电极设计和材料已成为微电极阵列日益重要的性能驱动因素，微电极阵列是细胞电生理学的重要工具之一。目前的研究工作在各种电极形状、尺寸和材料方面不断创新。庞大的设计和制造参数空间为优化性能和功能提供了丰富的机会，但由于缺乏用于辅助设计工作的预测模拟软件，这也给电极开发者带来了挑战。电极原型通常需要制造、进行经验评估并反复优化，成本高昂。因此，高效的硬件测试解决方案对于辅助新型电极的开发变得越来越重要，尤其是在候选设计数量仍然众多的早期阶段。在此，我们提出并实现了一个具有成本效益的测试平台，旨在从电极原型中获取一阶特性，以指导早期筛选和优化。在用微加工电极进行测试时，该平台显示出与商业设备相当的阻抗测量精度，并有效地记录了体外大鼠皮质神经元的细胞外动作电位。与现有硬件解决方案相比，该测试平台以显著更低的成本、更紧凑的形式以及更高的组装便利性提供相关电极测试，能够切实降低基于阵列的新型电生理微电极开发的入门门槛。
