Novel Approach for the Immobilization of Cellobiose Dehydrogenase in PEDOT:PSS Conductive Layer on Planar Gold Electrodes

Esra Cihan, Eva Melnik (Corresponding author), Steffen Kurzhals, Paulina Plata, Giorgio C. Mutinati (Corresponding author), Rainer Hainberger, Alfons K.G. Felice, Christopher Schulz, Peter Lieberzeit (Corresponding author)

Publications: Contribution to journalArticlePeer Reviewed

Abstract

Third-generation biosensors use enzymes capable of direct electron transfer (DET) to the sensor surface. They are of interest for continuous glucose monitoring in blood or interstitial fluid, but they are rarely investigated. One reason is the hindered DET of the enzymes to the metallic electrodes. In this publication, a novel method for the immobilization of cellobiose dehydrogenase (CDH) DET enzymes employing conductive poly(3,4-ethylenedioxythiophene)-poly (styrene sulfonate) (PEDOT:PSS) inks and a protective polyethylene glycol dimethacrylate (PEG-DMA) hydrogel layer on gold electrodes is reported. This layer stack showed a glucose-specific current response for voltages between −0.2 and 0.4 V in physiological PBS buffer, and enabled interference-less sensing in a solution of acetaminophen, ascorbic acid, dopamine, and uric acid at 0 V. A Michaelis–Menten fit led to a maximum current density (Imax) of 257 ± 7.9 nA/mm2 and a Michaelis–Menten constant (Km) of 28.4 ± 2.2 mM, with a dynamic range of 0.1–20 mM glucose and a limit of detection of 0.1 mM. After 16 h of continuous measurement of 20 mM glucose, the signal decreased to 60% of its initial value. Storage stability was successfully verified until up to 10 days. In summary, this paper shows a simplified approach for the fabrication of third-generation biosensors using CDH-PEDOT:PSS and PEG-DMA hydrogel inks.

Original languageEnglish
Article number36
JournalChemosensors
Volume12
Issue number3
DOIs
Publication statusPublished - Mar 2024

Austrian Fields of Science 2012

  • 104017 Physical chemistry
  • 202036 Sensor systems
  • 104002 Analytical chemistry

Keywords

  • biosensors
  • cellobiose dehydrogenase
  • conductive polymer
  • DET enzymes
  • PEDOT:PSS

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