title: Smart Metal-Organic Framework Coatings: Triggered Antibiofilm Compound Release.
abstract: Metal-organic frameworks (MOFs) have a large potential for delivery of active molecules. Here, a MOF coating is investigated as a smart host matrix for triggered release of antibiofilm compounds. In addition to a coating consisting of the regular Fe-terephthalate MIL-88B(Fe), a new hydrophobic MIL-88B(Fe) coating is synthesized in hydrothermal conditions using palmitic acid as a lattice terminating group. These porous materials are used as a host matrix for the antibiofilm compound 5-(4-chlorophenyl)-N-(2-isobutyl)-2-aminoimidazole, which has a specific biofilm-inhibiting effect at concentrations at which no activity against planktonic cells is detected. The stability of MIL-88B(Fe) in distilled water and tryptic soy broth medium is investigated, together with the ability of iron(III) chelators to serve as a trigger for controlled decomposition of MIL-88B(Fe) by metal complexation. Organic iron chelators are used to mimic the iron chelating function of siderophores, which are specific molecules excreted by biofilm-forming bacteria. Trisodium citrate is able to chelate metal ions from the junctions of the framework. By sequestration of these metal ions, the host matrix is partially degraded, resulting in an antibiofilm compound release. Finally, the antibiofilm properties against Salmonella Typhimurium are validated by monitoring biofilm growth on MOF layers either loaded or not with aminoimidazole. A strong proof-of-concept is shown for efficient inhibition of biofilm growth through triggered antibiofilm compound release.
authors.affiliation: Centre for Surface Chemistry and Catalysis, KU Leuven , Kasteelpark Arenberg 23, 3001 Leuven, Belgium.
authors.forename: Birgit
authors.identifier: http://orcid.org/0000-0002-8851-0739
authors.initials: B
authors.lastname: Claes
authors.affiliation: Centre for Surface Chemistry and Catalysis, KU Leuven , Kasteelpark Arenberg 23, 3001 Leuven, Belgium.
authors.forename: Tom
authors.initials: T
authors.lastname: Boudewijns
authors.affiliation: Centre for Surface Chemistry and Catalysis, KU Leuven , Kasteelpark Arenberg 23, 3001 Leuven, Belgium.
authors.forename: Laurens
authors.initials: L
authors.lastname: Muchez
authors.affiliation: Molecular Design and Synthesis, KU Leuven , Celestijnenlaan 200F, 3001 Leuven, Belgium.
authors.forename: Geert
authors.initials: G
authors.lastname: Hooyberghs
authors.affiliation: Molecular Design and Synthesis, KU Leuven , Celestijnenlaan 200F, 3001 Leuven, Belgium.
authors.forename: Erik V
authors.initials: EV
authors.lastname: Van der Eycken
authors.affiliation: Centre for Microbial and Plant Genetics, KU Leuven , Kasteelpark Arenberg 20, 3001 Leuven, Belgium.
authors.forename: Jozef
authors.initials: J
authors.lastname: Vanderleyden
authors.affiliation: Centre for Microbial and Plant Genetics, KU Leuven , Kasteelpark Arenberg 20, 3001 Leuven, Belgium.
authors.forename: Hans P
authors.initials: HP
authors.lastname: Steenackers
authors.affiliation: Centre for Surface Chemistry and Catalysis, KU Leuven , Kasteelpark Arenberg 23, 3001 Leuven, Belgium.
authors.forename: Dirk E
authors.initials: DE
authors.lastname: De Vos
mesh_terms: D005290:Ferric Compounds; D007501:Iron; D000073396:Metal-Organic Frameworks / Q000737:chemistry*; D014867:Water
chemical_list: D005290:Ferric Compounds; D000073396:Metal-Organic Frameworks; D014867:Water; D007501:Iron
keywords: Salmonella; active molecule release; biofilm; iron; metal−organic framework; stimulus responsive