Enzymatic fuel cells with an oxygen resistant variant of pyranose-2-oxidase as anode biocatalyst

Abstract

In enzymatic fuel cells (EnFCs), hydrogen peroxide formation is one of the main problems when enzymes, such as, glucose oxidase (GOx) is used due to the conversion of oxygen to hydrogen peroxide in the catalytic reaction. To address this problem, we here report the first demonstration of an EnFC using a variant of pyranose-2-oxidase (P2O-T169G) which has been shown to have low activity towards oxygen. A simple and biocompatible immobilisation approach incorporating multi-walled-carbon nanotubes within ferrocene (Fc)-Nafion film was implemented to construct EnFCs. Successful immobilisation of the enzymes was demonstrated showing 3.2 and 1.7-fold higher current than when P2O-T169G and GOx were used in solution, respectively. P2O-T169G showed 25% higher power output (maximum power density value of 8.45 ± 1.6 μW cm) and better stability than GOx in aerated glucose solutions. P2O-T169G maintained > 70% of its initial current whereas GOx lost activity > 90% during the first hour of 12 h operation at 0.15 V (vs Ag/Ag). A different fuel cell configuration using gas-diffusion cathode and carbon paper electrodes were used to improve the power output of the fuel cell to 29.8 ± 6.1 µW cm. This study suggests that P2O-T169G with low oxygen activity could be a promising anode biocatalyst for EnFC applications.

The Mechanism of Sugar C−H Bond Oxidation by a Flavoprotein Oxidase Occurs by a Hydride Transfer Before Proton Abstraction

“…P2O is among the most useful sugar‐specific biocatalysts for industrial applications because it can catalyze regiospecific oxidative transformation of aldoses into 2‐keto‐aldoses, which are precursors for the synthesis of valuable compounds such as fructose, tagatose, isoascorbic acid or the antibiotic cortalcerone . P2O is also attractive for applications in the fields of biosensors and biofuel cells . P2O from various species have been investigated and the enzyme from Trametes multicolor has been most extensively studied.…”

A simple and sensitive hydrogen peroxide detection with horseradish peroxidase immobilized on pyrene modified acid‐treated single‐walled carbon nanotubes

“…Each method has its challenge and its advantages depending on the biomolecule used. However, non‐covalent binding of biomolecules to carbon nanotubes using strong π–π interactions between the sidewall of the nanotube and the biomolecule is a successful immobilization strategy . Pyrene and its derivatives are mostly utilized to achieve biomolecule immobilization while providing a range of different possibilities.…”

“…Pyrene and its derivatives are mostly utilized to achieve biomolecule immobilization while providing a range of different possibilities. Since carbon nanomaterials have a very large surface area, successful crosslinking can be achieved with better conductivity using pyrene derivatives . In our previous study, immobilization of a different enzyme on carbon nanostructured screen‐printed electrodes (SPEs) and carbon paper was successfully achieved using pyrene‐based crosslinking chemistry …”

Polyethyleneimine Modified Carbon Cloth Anode for Self-Pumping Enzymatic Glucose Biofuel Cell

“…In 2016, Yang et al [12] improved the GOx retained activity in the optimum pH 7.0-7.2 range. Moreover, most EBC performance tests with the glucose solution pH 7 as the anode inlet fuel supplied have been studied [2,10,[13][14][15][16]. This study utilizes PEI to enhance GOx enzyme immobilization.…”