title: Covalent coating of hydroxyapatite by keratin stabilizes gentamicin release.
abstract: A novel hybrid hydroxyapatite (HAP) matrix, covalently coated with rarely applied, hardly degradable keratin and effectively modified by gentamicin immobilized in mixed-type mode (via interactions of diverse strength), was created. This hybrid showed a remarkably high drug immobilization yield and the most sustainable antibiotic release among all tested composites. It was also able to inhibit bacterial growth, both in surrounding liquid and on matrix surface, much longer (for at least 121 days of experiment) than analogous gelatin-modified and nonmodified matrices. Gentamicin-keratin-coated-HAP granules were nontoxic to human osteoblasts and enabled their proliferation with a rate similar as noncoated HAP. Presence of keratin on HAP granules seemed to slightly enhance the osteoblast proliferation. The results indicate that newly created HAP hybrid with covalently immobilized keratin and gentamicin--nontoxic and osteoblast-friendly--is a promising biomaterial of significantly prolonged antibacterial activity.
authors.affiliation: Department of Biochemistry, Medical University of Lublin, Lublin, Poland. anna.belcarz@am.lublin.pl
authors.forename: Anna
authors.initials: A
authors.lastname: Belcarz
authors.forename: Grazyna
authors.initials: G
authors.lastname: Ginalska
authors.forename: Justyna
authors.initials: J
authors.lastname: Zalewska
authors.forename: Wojciech
authors.initials: W
authors.lastname: Rzeski
authors.forename: Anna
authors.initials: A
authors.lastname: Slósarczyk
authors.forename: Dorota
authors.initials: D
authors.lastname: Kowalczuk
authors.forename: Piotr
authors.initials: P
authors.lastname: Godlewski
authors.forename: Justyna
authors.initials: J
authors.lastname: Niedźwiadek
mesh_terms: D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism*; D002460:Cell Line; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000378:metabolism; D004337:Drug Carriers / Q000737:chemistry / Q000378:metabolism; D016503:Drug Delivery Systems; D017886:Durapatite / Q000737:chemistry*; D005839:Gentamicins / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D007633:Keratins / Q000737:chemistry*; D008422:Materials Testing; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D013499:Surface Properties
chemical_list: D000900:Anti-Bacterial Agents; D020099:Coated Materials, Biocompatible; D004337:Drug Carriers; D005839:Gentamicins; D007633:Keratins; D017886:Durapatite