title: Design of Stable and Powerful Nanobiocatalysts, Based on Enzyme Laccase Immobilized on Self-Assembled 3D Graphene/Polymer Composite Hydrogels.
abstract: Graphene-based materials appear as a suitable answer to the demand for novel nanostructured materials for effective nanobiocatalytic systems design. In this work, a design of stable and efficient nanobiocatalysts made of enzyme laccase immobilized on composite hydrogels [reduced graphene oxide (rGO)/polymer] is presented. The composite hydrogel supports were synthesized by self-assembly of graphene oxide nanoplatelets in the frame of a polymer latex matrix, where the polymer nanoparticles were adsorbed onto the GO surface, creating hybrid nanoplatelets. These hybrids self-assembled when ascorbic acid was added as a GO reducing agent and formed three-dimensional porous structures, greatly swollen with water, e.g., the composite hydrogels. The hydrogels were used as a support for covalent immobilization of the laccase. The performance of the nanobiocatalysts was tested in the oxidative degradation of the recalcitrant synthetic dye Remazol Brilliant Blue R in aqueous solutions. The biocatalysts showed strong dye discoloration ability and high stability as they preserved their catalytic action in four successive batches of dye degradation. The presented biocatalysts offer possibilities for overcoming the main disadvantages of the enzyme catalysts (fragile nature, high cost, and high loading of the enzyme), which would lead to a step forward toward their industrial application.
authors.affiliation: †POLYMAT and Departamento de Química Aplicada, Facultad de Ciencias Químicas, University of the Basque Country, UPV/EHU, Donostia-San Sebastián, Spain.
authors.forename: Nerea
authors.initials: N
authors.lastname: Ormategui
authors.affiliation: †POLYMAT and Departamento de Química Aplicada, Facultad de Ciencias Químicas, University of the Basque Country, UPV/EHU, Donostia-San Sebastián, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Veloso
authors.affiliation: †POLYMAT and Departamento de Química Aplicada, Facultad de Ciencias Químicas, University of the Basque Country, UPV/EHU, Donostia-San Sebastián, Spain.
authors.forename: Gracia Patricia
authors.initials: GP
authors.lastname: Leal
authors.affiliation: ‡CEIT, Unit of Environmental Engineering, Paseo Manuel de Lardizábal, Donostia-San Sebastián, Spain.|§IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Rodriguez-Couto
authors.affiliation: †POLYMAT and Departamento de Química Aplicada, Facultad de Ciencias Químicas, University of the Basque Country, UPV/EHU, Donostia-San Sebastián, Spain.|§IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
authors.forename: Radmila
authors.initials: R
authors.lastname: Tomovska
mesh_terms: D001673:Biodegradation, Environmental; D019149:Bioreactors; D004396:Coloring Agents / Q000032:analysis / Q000378:metabolism; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D006108:Graphite / Q000737:chemistry*; D020100:Hydrogels / Q000737:chemistry*; D042845:Laccase / Q000737:chemistry / Q000378:metabolism; D053761:Nanocomposites / Q000737:chemistry*; D016062:Porosity
chemical_list: D004396:Coloring Agents; D004800:Enzymes, Immobilized; D020100:Hydrogels; D006108:Graphite; D042845:Laccase
keywords: Remazol Brilliant Blue R; graphene 3D monoliths; graphene hydrogels; laccase; nanobiocatalyst; porous monoliths; self-assembled graphene structures