Fundamentals and Applications of Redox Enzyme-functionalized Electrode Reactions

Abstract

Electrochemical coupling of redox enzyme reactions, called bioelectrocatalysis, has been attracting great attention over the last four decades. It has become an important technology that can be applied to a wide range of bioelectrochemical devices including biosensors, biofuel cells, and bioreactors. This article presents an overview of the basic concepts of steady-state catalytic waves of mediated-and direct electron transfer (DET)-type bioelectrocatalysis. Several equations that can be used for the analysis of steady-state waves are introduced. The analysis may provide important thermodynamic and kinetic parameters that can be used not only for performance evaluation of the devices but also for fundamental research on the enzymes. Important progress made on how to tune electrode surfaces and enzymes for DET-type reactions are presented. Applications to bioelectrochemical devices are also summarized with emphasis on the achievements recorded in our research group.

A Modifiable, Spontaneously Formed Polymer Gel with Zwitterionic and N-Hydroxysuccinimide Moieties for an Enzymatic Biofuel Cell

“…However, as the difference between the two redox potentials (driving force of the reaction) becomes larger, the reaction rate constant between the enzyme and the mediator becomes exponentially higher according to the linear free energy relationship. 42 Thus, before the potential-independent region, the positive shift of redox potential of the mediator would lead to a higher reaction rate between the enzyme and the mediator. The output current would be higher at the expense of higher overpotential.…”

Recent Progress in Applications of Enzymatic Bioelectrocatalysis

“…Therefore, nanostructured electrodes with a large ratio of the effective surface area against the projective surface area are useful and frequently utilized for bioelectrocatalytic systems. In addition, it is suggested that the heterogeneous electron transfer kinetics at the top edge of the microstructures of these electrodes is accelerated by the electric field strengthened by the expansion of the electric double layer [56] and the charge accumulation as expected by the Poisson equation [4]. This effect is very useful to decrease the overpotential due to the heterogeneous electron transfer in the DET-type reaction.…”

“…The coupled reaction is called bioelectrocatalysis, and the catalytic function of the redox enzymes provides a variety of specific and strong catalytic activities to nonspecific electrode reactions. [1][2][3][4][5]. Bioelectrocatalysis provides a firm base for characterizing redox enzyme reactions and applying the concept and related technologies to useful bioelectrochemical devices such as biosensors [6][7][8][9][10][11][12][13][14], biofuel cells [11,[15][16][17][18][19][20][21], biosupercapacitors [22], and other bioreactors [23].…”

Development Perspective of Bioelectrocatalysis-Based Biosensors

“…The coupling of redox enzymatic reactions with electrochemical reactions has received worldwide medical and scientific interests [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ]. The coupled reaction is called bioelectrocatalysis.…”