Latorre Malcolm A, Chan Adrian D C, Wårdell Karin
Department of Biomedical Engineering, Linköping University Linköping, Sweden.
Department of Systems and Computer Engineering, Carleton University Ottawa, ON, Canada.
Front Neurosci. 2015 Oct 20;9:371. doi: 10.3389/fnins.2015.00371. eCollection 2015.
The objective was to develop a physical action potential generator (Paxon) with the ability to generate a stable, repeatable, programmable, and physiological-like action potential. The Paxon has an equivalent of 40 nodes of Ranvier that were mimicked using resin embedded gold wires (Ø = 20 μm). These nodes were software controlled and the action potentials were initiated by a start trigger. Clinically used Ag-AgCl electrodes were coupled to the Paxon for functional testing. The Paxon's action potential parameters were tunable using a second order mathematical equation to generate physiologically relevant output, which was accomplished by varying the number of nodes involved (1-40 in incremental steps of 1) and the node drive potential (0-2.8 V in 0.7 mV steps), while keeping a fixed inter-nodal timing and test electrode configuration. A system noise floor of 0.07 ± 0.01 μV was calculated over 50 runs. A differential test electrode recorded a peak positive amplitude of 1.5 ± 0.05 mV (gain of 40x) at time 196.4 ± 0.06 ms, including a post trigger delay. The Paxon's programmable action potential like signal has the possibility to be used as a validation test platform for medical surface electrodes and their attached systems.
目标是开发一种物理动作电位发生器（Paxon），使其能够产生稳定、可重复、可编程且类似生理的动作电位。Paxon有相当于40个郎飞结的结构，这些郎飞结是用树脂包埋的金线（直径 = 20μm）模拟的。这些节点由软件控制，动作电位由启动触发器引发。临床使用的Ag-AgCl电极与Paxon相连进行功能测试。Paxon的动作电位参数可使用二阶数学方程进行调节，以产生生理相关的输出，这是通过改变参与的节点数量（以1为增量步长，从1到40）和节点驱动电位（以0.7mV步长，从0到2.8V）来实现的，同时保持固定的节点间定时和测试电极配置。在50次运行中计算出系统本底噪声为0.07±0.01μV。一个差分测试电极在196.4±0.06ms（包括触发后延迟）时记录到峰值正振幅为1.5±0.05mV（增益为40倍）。Paxon的可编程动作电位样信号有可能用作医疗表面电极及其附属系统的验证测试平台。
