Title Scanning electrochemical impedance microscopy in redox-competition mode for the investigation of antibodies labelled with horseradish peroxidase /
Authors Zinovičius, Antanas ; Morkvėnaitė-Vilkončienė, Inga ; Ramanavičienė, Almira ; Rožėnė, Justė ; Popov, Anton ; Ramanavičius, Arūnas
DOI 10.3390/ma14154301
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Is Part of Materials: Special issue: Recent advances in nanomaterials for biosensing applications.. Basel : MDPI. 2021, vol. 14, iss. 15, art. no. 4301, p. 1-8.. ISSN 1996-1944
Keywords [eng] scanning electrochemical microscopy ; antigen-antibody complex ; horseradish peroxidase ; immunoassay ; electrochemical methods ; electrochemical impedance spectroscopy ; bioelectrochemistry ; bioelectronics ; ultra-micro electrode ; scanning electrochemical impedance microscopy
Abstract [eng] Scanning electrochemical microscopy enhanced by electrochemical impedance spectroscopy (SEIM) was applied to detect immobilized antibodies labelled with horseradish peroxidase (Ab-HRP). The localized HRP activity was investigated by the SEIM redox competition (RC-SEIM) mode using hydrogen peroxide as a substrate and hexacyanoferrate as a redox mediator. Electrochemical impedance shows to be related to the consumption of hydrogen peroxide at the ultramicroelectrode. For the evaluation of impedimetric results, an equivalent electric circuit was applied with solution resistance, double-layer capacitance, and charge-transfer resistance. These equivalent circuit characteristics depend on the distance between the sample and ultramicroelectrode, and the concentration of substrate. From the gathered data, the charge-transfer resistance appeared to be the parameter describing the behavior of HRP catalyzed reaction as it showed a linear dependence on H2O2 concentration. The RC-SEIM mode suitability for the studying of HRP catalyzed reactions and for the evaluation of Ab-HRP bound to the surface was demonstrated. Additionally, the applicability of RC-SEIM mode for the determination of Ab-HRP affinity bound to the target analyte was discussed.
Published Basel : MDPI
Type Journal article
Language English
Publication date 2021
CC license CC license description