Title Electrochemical detection of choline via oxygen consumption in a thermally reduced graphene oxide matrix: Advantages of operation at both positive and negative potentials
Authors Šakinytė-Urbikienė, Ieva ; Butkevičius, Marius ; Gurevičienė, Vidutė ; Galuzinska, Liubov ; Razumienė, Julija
DOI 10.1016/j.sbsr.2025.100927
Full Text Download
Is Part of Sensing and Bio-Sensing Research.. Amsterdam : Elsevier. 2025, vol. 50, art. no. 100927, p. [1-7].. ISSN 2214-1804
Keywords [eng] Amperometric biosensor ; Choline oxidase ; TRGO ; Mechanism of choline bioelectrocatalysis ; ORR
Abstract [eng] An amperometric choline biosensor was developed using synthesised thermally reduced graphene oxide (TRGO) as an efficient electrochemical surface and immobilisation matrix for choline oxidase (ChOx). The biosensor can operate via two distinct mechanisms depending on the applied working electrode potential: dissolved oxygen (O₂) consumption at −0.3 V and hydrogen peroxide oxidation at +0.6 V vs Ag/AgCl. Under these conditions, the TRGO/ChOx biosensor exhibited a linear response to choline concentrations of 0.0009–0.24 mM and 0.0008–0.24 mM, with sensitivities of 29 and 38 μA mM−1 cm−2 at −0.3 V and + 0.6 V vs Ag/AgCl, respectively. Operation at −0.3 V significantly improved biosensor selectivity by minimizing interference from common biological species, including dopamine, adenosine, serotonin, uric acid, ascorbic acid, glucose, albumin, and epinephrine. The TRGO/ChOx biosensor demonstrated excellent accuracy in mouse urine samples, yielding recovery rates of 101–107 % and relative standard deviations of 0.4–3.9 %. These features, including the dual operating mechanisms, highlight the strong potential of this biosensor for rapid and reliable choline detection in non-invasive diagnostics.
Published Amsterdam : Elsevier
Type Journal article
Language English
Publication date 2025
CC license CC license description