title: Enzymatic functionalization of cork surface with antimicrobial hybrid biopolymer/silver nanoparticles.
abstract: Laccase-assisted assembling of hybrid biopolymer-silver nanoparticles and cork matrices into an antimicrobial material with potential for water remediation is herein described. Amino-functional biopolymers were first used as doping agents to stabilize concentrated colloidal dispersions of silver nanoparticles (AgNP), additionally providing the particles with functionalities for covalent immobilization onto cork to impart a durable antibacterial effect. The solvent-free AgNP synthesis by chemical reduction was carried out in the presence of chitosan (CS) or 6-deoxy-6-(ω-aminoethyl) aminocellulose (AC), leading to simultaneous AgNP biofunctionalization. This approach resulted in concentrated hybrid NP dispersion stable to aggregation and with hydrodynamic radius of particles of about 250 nm. Moreover, laccase enabled coupling between the phenolic groups in cork and amino moieties in the biopolymer-doped AgNP for permanent modification of the material. The antibacterial efficiency of the functionalized cork matrices, aimed as adsorbents for wastewater treatment, was evaluated against Escherichia coli and Staphylococcus aureus during 5 days in conditions mimicking those in constructed wetlands. Both intrinsically antimicrobial CS and AC contributed to the bactericidal effect of the enzymatically grafted on cork AgNP. In contrast, unmodified AgNP were easily washed off from the material, confirming that the biopolymers potentiated a durable antibacterial functionalization of the cork matrices.
authors.affiliation: †Grup de Biotecnologia Molecular i Industrial, Department of Chemical Engineering, Universitat Politècnica de Catalunya, 08222 Terrassa, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Francesko
authors.affiliation: ‡Grupo Interdisciplinario de Estudios Moleculares, Instituto de Química, Universidad de Antioquia, Medellín, Colombia.
authors.forename: Lucas
authors.initials: L
authors.lastname: Blandón
authors.affiliation: ‡Grupo Interdisciplinario de Estudios Moleculares, Instituto de Química, Universidad de Antioquia, Medellín, Colombia.
authors.forename: Mario
authors.initials: M
authors.lastname: Vázquez
authors.affiliation: †Grup de Biotecnologia Molecular i Industrial, Department of Chemical Engineering, Universitat Politècnica de Catalunya, 08222 Terrassa, Spain.
authors.forename: Petya
authors.initials: P
authors.lastname: Petkova
authors.affiliation: §AQUASOST Group - UNESCO Chair on Sustainability, Universitat Politècnica de Catalunya, 08034 Barcelona, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Morató
authors.affiliation: ∥Center of Excellence for Polysaccharide Research, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich Schiller University of Jena, 07743 Jena, Germany.
authors.forename: Annett
authors.initials: A
authors.lastname: Pfeifer
authors.affiliation: ∥Center of Excellence for Polysaccharide Research, Institute of Organic Chemistry and Macromolecular Chemistry, Friedrich Schiller University of Jena, 07743 Jena, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Heinze
authors.affiliation: ⊥Grup de Nanomaterials Aplicats. Centre de Recerca en Nanoenginyeria, Universitat Politècnica de Catalunya, 08222 Terrassa, Spain.
authors.forename: Ernest
authors.initials: E
authors.lastname: Mendoza
authors.affiliation: †Grup de Biotecnologia Molecular i Industrial, Department of Chemical Engineering, Universitat Politècnica de Catalunya, 08222 Terrassa, Spain.
authors.forename: Tzanko
authors.initials: T
authors.lastname: Tzanov
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D001704:Biopolymers / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects; D057446:Hydrodynamics; D042845:Laccase / Q000378:metabolism*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008826:Microbial Sensitivity Tests; D012834:Silver / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013211:Staphylococcus aureus / Q000187:drug effects; D055672:Static Electricity; D013499:Surface Properties
chemical_list: D000890:Anti-Infective Agents; D001704:Biopolymers; D012834:Silver; D042845:Laccase
keywords: amino-functional biopolymers; antimicrobial activity; cork; enzymatic grafting; silver nanoparticles