Choosing the right electrode representation for modeling real bioelectronic interfaces: a comprehensive guide

Scientific paper - Original scientific paper

• Author: Aleksandar Opančar
• Author: Eric Daniel Głowacki
• Author: Vedran Đerek
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

Producing realistic numerical models of neurostimulation electrodes in contact with the electrolyte and tissue, for use in time-domain finite element method simulations while maintaining a reasonable computational burden remains a challenge. We aim to provide a straightforward experimental-theoretical hybrid approach for common electrode materials (Ti, TiN, ITO, Au, Pt, IrOx) that are relevant to the research field of bioelectronics, along with all the information necessary to replicate our approach in arbitrary geometry for real-life experimental applications. We used electrochemical impedance spectroscopy (EIS) to extract the electrode parameters in the AC regime under different DC biases. The pulsed electrode response was obtained by fast amperometry (FA) to optimize and verify the previously obtained electrode parameters in a COMSOL Multiphysics model. For optimization of the electrode parameters a constant phase element (CPE) needed to be implemented in time-domain. We find that the parameters obtained by EIS can be used to accurately simulate pulsed response only close to the electrode open circuit potential, while at other potentials we give corrections to the obtained parameters, based on FA measurements. We also find that for many electrodes (Au, TiN, Pt, and IrOx), it is important to implement a distributed CPE rather than an ideal capacitor for estimating the electrode double-layer capacitance. We outline and provide examples for the novel time-domain implementation of the CPE for finite element method simulations in COMSOL Multiphysics. An overview of electrode parameters for some common electrode materials can be a valuable and useful tool in numerical bioelectronics models. A provided FEM implementation model can be readily adapted to arbitrary electrode geometries and used for various applications. Finally, the presented methodology for parametrization of electrode materials can be used for any materials of interest which were not covered by this work.

• Keywords (english): bioelectronics; electrodes; interface; constant phase element; simulation
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Journal of Neural Engineering
• Numbering: vol. 21, no. 4, 046049
• p-ISSN: 1741-2560
• e-ISSN: 1741-2552
• DOI: https://doi.org/10.1088/1741-2552/ad6a8b
• URN:NBN: urn:nbn:hr:217:179432
• Publication: 2024-08-14
• Project: Number: UIP-2019-04-1753; Title (croatian): Mikro i nano-strukture za 3D opto-bioelektroniku; Title (english): Micro- and nano-structures for 3D opto-bioelectronics; Acronym: 3Doptobio; Leader: Vedran Đerek; Jurisdiction: Croatia; Funding stream: Installation Research Projects
• Project: Number: KK.01.1.1.02.0013; Title (croatian): Centar za Napredna Istraživanja Kompleksnih Sustava; Title (english): Centre for Advanced Research of Complex Systems; Acronym: CeNIKS; Leader: Mihael Srđan Grbić; Jurisdiction: eu; Funding stream: European Regional Development Fund
• Project: Number: KK.01.1.1.01.0004; Title (croatian): Provedba vrhunskih istraživanja u sklopu Znanstvenog centra izvrsnosti za kvantne i kompleksne sustave te reprezentacije Liejevih algebri; Title (english): Implementation of top research within the Scientific Center of Excellence for Quantum and Complex Systems, and Representations of Lie Algebras; Acronym: QuantiXLie; Leader: Hrvoje Buljan; Jurisdiction: eu; Funding stream: European Regional Development Fund
• Document URL: https://iopscience.iop.org/article/10.1088/1741-2552/ad6a8b
• Type of resource: Text
• Access conditions: Open access
• Public note: © 2024 The Author(s). Published by IOP Publishing Ltd. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Received 28 February 2024; Revised 12 July 2024; Accepted for publication 1 August 2024; Published 14 August 2024.
• Created on: 2024-08-23 08:50:40