Elliptical fitting as an alternative approach to complex nonlinear least squares regression for modeling electrochemical impedance spectroscopy

Pfeiffer N, Wachter T, Frickel J, Hofmann C, Errachid A, Heuberger A (2021)

Publication Type: Conference contribution

Publication year: 2021

Publisher: SciTePress

Pages Range: 42-49

Conference Proceedings Title: BIOSIGNALS 2021 - 14th International Conference on Bio-Inspired Systems and Signal Processing; Part of the 14th International Joint Conference on Biomedical Engineering Systems and Technologies, BIOSTEC 2021

ISBN: 9789897584909

Abstract

Electrochemical impedance spectroscopy is an important procedure with the ability to describe a wide range of physical and chemical properties of electrochemical systems. The spectral behavior of impedimetric sensors is mostly described by the Randles circuit, whose parameters are determined by regression techniques on the basis of measured spectra. The charge transfer resistance as one of these parameters is often used as sensor response. In the laboratory environment, the regression is usually performed by commercial software, but for integrated, application-oriented solutions, separate approaches must be pursued. This work presents an approach for elliptical fitting of the curve in the Nyquist plot, which is compared to the complex nonlinear least squares (CNLS) regression technique. For this purpose, artificial spectra were generated, which were considered both with and without noise superposition. Although the average error in calculating the charge transfer resistance from noisy signals using the elliptical fitting of −2.7% was worse than the CNLS with 2.4 · 10−2%, the former required only about 1/225 of the computing time compared to the latter. Following application-oriented evaluations of the achievable accuracies, the elliptical approach may turn out to be a resource saving alternative.

Authors with CRIS profile

Jürgen Frickel Lehrstuhl für Informationstechnik mit dem Schwerpunkt Kommunikationselektronik (Stiftungslehrstuhl) Albert Heuberger Lehrstuhl für Informationstechnik mit dem Schwerpunkt Kommunikationselektronik (Stiftungslehrstuhl)

Involved external institutions

Fraunhofer-Institut für Integrierte Systeme und Bauelementetechnologie (IISB) DE Germany (DE) Université de Lyon (UDL) FR France (FR)

How to cite

APA:

Pfeiffer, N., Wachter, T., Frickel, J., Hofmann, C., Errachid, A., & Heuberger, A. (2021). Elliptical fitting as an alternative approach to complex nonlinear least squares regression for modeling electrochemical impedance spectroscopy. In Bethany Bracken, Ana Fred, Hugo Gamboa (Eds.), BIOSIGNALS 2021 - 14th International Conference on Bio-Inspired Systems and Signal Processing; Part of the 14th International Joint Conference on Biomedical Engineering Systems and Technologies, BIOSTEC 2021 (pp. 42-49). SciTePress.

MLA:

Pfeiffer, Norman, et al. "Elliptical fitting as an alternative approach to complex nonlinear least squares regression for modeling electrochemical impedance spectroscopy." Proceedings of the 14th International Conference on Bio-Inspired Systems and Signal Processing, BIOSIGNALS 2021 - Part of the 14th International Joint Conference on Biomedical Engineering Systems and Technologies, BIOSTEC 2021 Ed. Bethany Bracken, Ana Fred, Hugo Gamboa, SciTePress, 2021. 42-49.

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