Eco-Friendly Composite of Fe₃O₄-Reduced Graphene Oxide Particles for Efficient Enzyme Immobilization

Abstract

A novel type of spherical and porous composites were synthesized to dually benefit from reduced graphene oxide (rGO) and magnetic materials as supports for enzyme immobilization. Three magnetic composite particles of FeO and rGO containing 71% (rGO-FeO-M1), 36% (rGO-FeO-M2), and 18% (rGO-FeO-M3) Fe were prepared using a one-pot spray pyrolysis method and were used for the immobilization of the model enzymes, laccase and horseradish peroxidase (HRP). The rGO-FeO composite particles prepared by spray pyrolysis process had a regular shape, finite size, and uniform composition. The immobilization of laccase and HRP on rGO-FeO-M1 resulted in 112 and 89.8% immobilization efficiency higher than that of synthesized pure FeO and rGO particles, respectively. The stability of laccase was improved by approximately 15-fold at 25 °C. Furthermore, rGO-FeO-M1-immobilized laccase exhibited 92.6% of residual activity after 10 cycles of reuse and was 192% more efficient in oxidizing different phenolic compounds than the free enzyme. Therefore, these unique composite particles containing rGO and FeO may be promising supports for the efficient immobilization of industrially important enzymes with lower acute toxicity toward Vibrio fischeri than commercial pure FeO particles.

Nanoparticle‐Mediated Enzyme Immobilization on Cellulose Fibers: Reusable Biocatalytic Systems for Cascade Reactions

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Enhanced Saccharification and Fermentation of Rice Straw by Reducing the Concentration of Phenolic Compounds Using an Immobilized Enzyme Cocktail

“…Nanomaterial‐based supports for the covalent immobilization of enzymes showed a significant influence on the enzyme's properties due to their high surface area and unique structures . Additionally, the magnetic nature of the support allows for easy separation using a magnetic field . The covalent immobilization of enzymes resulted in strong interactions between the functional groups present on the surface of the support and enzymes to overcome the limitation of leaching, which have been primarily associated with the adsorption of enzymes on the support through week interactions .…”

“…Free enzymes are also unstable when they are isolated from their source. There are several methods to overcome this problem, such as enzyme immobilization . Immobilized enzyme mimics the natural mode of action, wherein it is attached to the support surface and is more robust to environmental changes as compared to free enzymes .…”

“…Immobilized enzyme mimics the natural mode of action, wherein it is attached to the support surface and is more robust to environmental changes as compared to free enzymes . It does not completely mix with the reaction mixture, improves the stability, and allows for easy recovery and multiple uses . It allows for the greatest return in terms of reducing the costs of the enzyme while increasing hydrolysis and sugar conversion.…”

Immobilization of laccase onto modified PU/RC nanofiber via atom transfer radical polymerization method and application in removal of bisphenol A

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