title: A physical action potential generator: design, implementation and evaluation.
abstract: 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.
authors.affiliation: Department of Biomedical Engineering, Linköping University Linköping, Sweden.
authors.forename: Malcolm A
authors.initials: MA
authors.lastname: Latorre
authors.affiliation: Department of Systems and Computer Engineering, Carleton University Ottawa, ON, Canada.
authors.forename: Adrian D C
authors.initials: AD
authors.lastname: Chan
authors.affiliation: Department of Biomedical Engineering, Linköping University Linköping, Sweden.
authors.forename: Karin
authors.initials: K
authors.lastname: Wårdell
keywords: action potential; biomedical electrode; electronic nerve model; nodes of Ranvier; ulnar nerve