Advances in enzyme bioelectrochemistry

Abstract

Bioelectrochemistry can be defined as a branch of Chemical Science concerned with electron-proton transfer and transport involving biomolecules, as well as electrode reactions of redox enzymes. The bioelectrochemical reactions and system have direct impact in biotechnological development, in medical devices designing, in the behavior of DNA-protein complexes, in green-energy and bioenergy concepts, and make it possible an understanding of metabolism of all living organisms (e.g. humans) where biomolecules are integral to health and proper functioning. In the last years, many researchers have dedicated itself to study different redox enzymes by using electrochemistry, aiming to understand their mechanisms and to develop promising bioanodes and biocathodes for biofuel cells as well as to develop biosensors and implantable bioelectronics devices. Inside this scope, this review try to introduce and contemplate some relevant topics for enzyme bioelectrochemistry, such as the immobilization of the enzymes at electrode surfaces, the electron transfer, the bioelectrocatalysis, and new techniques conjugated with electrochemistry vising understand the kinetics and thermodynamics of redox proteins. Furthermore, examples of recent approaches in designing biosensors and biofuel developed are presented.

Electrochemical Biosensors Containing Pure Enzymes or Crude Extracts as Enzyme Sources for Pesticides and Phenolic Compounds with Pharmacological Property Detection and Quantification

“…These biosensors require the enzyme immobilization on the electrode surface. The most frequently used methods for enzyme immobilization are noncovalent adsorption, covalent bonding, entrapment, cross-linking, and affinity, and they are discussed below [14].…”

“…hydrogen bonds, and electrostatic interactions [14]. In contrast, in the covalent bonding immobilization, the enzyme is anchored on the electrode surface by multiple covalent bonds between support functional groups and enzymes.…”

“…Therefore, the enzymatic activity of the immobilized enzyme is decreased, when compared to native enzyme activity [15]. Cross-linking immobilization is an alternative, which requires the reaction between cross-linking protein molecules and a chemical cross-linker, usually glutaraldehyde [14]. The diversity of immobilization techniques allows the immobilization of enzymes in distinct materials, such as carbon nanostructures, (carbon black, nanotubes, and graphene and derivatives, among others), ceramic or polymeric matrices, and nanoparticles [16,17].…”

Nitric Oxide Detection Using Electrochemical Third‐generation Biosensors – Based on Heme Proteins and Porphyrins

“…. CS, a natural biopolymer, showed good biocompatibility, nontoxicity, excellent film forming ability and high mechanical strength to immobilize proteins and also to act as dispersant for nanomaterials . The interesting inherent properties of the CTAB surfactant were used to obtain a good dispersion of GR without particles aggregation.…”

A Flexible Nafion Coated Enzyme‐free Glucose Sensor Based on Au‐dimpled Ti Structures

“…The most of studied sensors are based on enzymatic oxidation of glucose to gluconolactone by glucose oxidase (GOx) and further amperometric detection of hydrogen peroxide by using various electron mediators (e. g. Prussian blue) [10]. However, performance of such enzymatic sensors is limited by characteristic features of an enzyme itself.…”