Horseradish Peroxidase Immobilized on Graphene Oxide: Physical Properties and Applications in Phenolic Compound Removal

Abstract

Composition, morphology, and surface characteristics of solid substrates play critical roles in regulating immobilized enzyme activity. Grapheme oxide (GO), a novel nanostructured material, has been illustrated as an ideal enzyme immobilization substrate due to its unique chemical and structural properties. Physical properties and catalytic activity of GO immobilized horseradish peroxidase (HRP) and its application in phenolic compound removal are described in the present study. HRP loading on GO was found to be much higher than that on reported substrates. The GO immobilized HRP showed improved thermal stability and a wide active pH range, attractive for practical applications. The removal of phenolic compounds from aqueous solution using the GO immobilized HRP was explored with seven phenolic compounds as model substrates. The GO immobilized HRP exhibited overall a high removal efficiency to several phenolic compounds in comparison to soluble HRP, especially for 2,4-dimetheoxyphenol and 2-chlorphenol, the latter a major component of industrial wastewater.

In situ synthesized rGO–Fe3O4 nanocomposites as enzyme immobilization support for achieving high activity recovery and easy recycling

“…6c), indicating an ease recycling attributes. [10,18,46]. The excellent activity recovery may be assigned to the magnetic−field effect of Fe3O4 at the nanoscale [47] and the high specific surface area of rGO nanosheets that can offer numerous contacting opportunities between enzyme and the substrate [46].…”

“…To date, various nanostructures, such as nanoparticle [7], nanofiber [8], nanotube [9] and nanosheet [10] have been explored as the support for enzyme immobilization. Among them, the graphene/graphene−based nanosheets have attracted much attention because of their unique structural features and exceptional chemical, electrical and mechanical properties [11][12][13].…”

Interactions of graphene and graphene oxide with proteins and peptides

“…GO used as a matrix for enzyme immobilization was first reported by Zhang et al [65,66] . Without using any cross-linking reagents, horseradish peroxidase (HRP) and lysozyme molecules were immobilized onto GO simply by incubating the GO sheets in a phosphate buffer containing the HRP or lysozyme.…”

Graphene oxide derivatives with variable alkyl chain length and terminal functional groups as supports for stabilization of cytochrome c

“…Moreover, the use of GO and its functionalized derivatives as nanoscaffolds for enzyme immobilization offers the possibility of manipulation of the microenvironment of the enzymes, enhancing their catalytic behavior and operational stability which result in the development of robust nanobiocalysts [10,11]. Various GONs have been employed for the immobilization of enzymes for the development of nanobiocatalytic systems with application in wastewater treatment [12], phenol compound removal [13], in situ protein digestion [14], as well as various biocatalytic transformations with industrial interest [15].…”