title: Creation of nanoporous TiO2 surface onto polyetheretherketone for effective immobilization and delivery of bone morphogenetic protein.
abstract: This study evaluated the utility of the creation of a nanoporous TiO2 surface to enhance the in vitro biocompatibility and in vivo osseoconductivity of polyetheretherketone (PEEK) implants by providing favorable sites for the effective immobilization of bone morphogenetic protein-2 (BMP-2). A uniform nanoporous TiO2 layer with a pore diameter of ∼70 nm was successfully created by anodizing a Ti film, which had been deposited onto a PEEK substrate via electron beam (e-beam) evaporation technique. This nanoporous, hydrophilic TiO2 surface enabled the efficient immobilization of BMP-2, resulting in a remarkable enhancement in in vitro biocompatibility that was assessed in terms of cell attachment, proliferation, and differentiation. The in vivo animal tests also confirmed that the nanoporous TiO2 surface immobilized with BMP-2 could significantly enhance the osseoconductivity of PEEK implants. The BMP-immobilized PEEK implant with the nanoporous TiO2 surface showed much higher bone-to-implant contact (BIC) ratio (60%) than the bare PEEK (30%), PEEK with the nanoporous TiO2 surface (50%) and even BMP-immobilized PEEK without the nanoporous TiO2 surface (32%).
authors.affiliation: WCU Hybrid Materials Program, Department of Materials Science and Engineering, Seoul National University, Seoul, 151-744, Korea.
authors.forename: Cheol-Min
authors.initials: CM
authors.lastname: Han
authors.forename: Tae-Sik
authors.initials: TS
authors.lastname: Jang
authors.forename: Hyoun-Ee
authors.initials: HE
authors.lastname: Kim
authors.forename: Young-Hag
authors.initials: YH
authors.lastname: Koh
mesh_terms: D016475:3T3 Cells; D000818:Animals; D001577:Benzophenones; D055396:Bone Morphogenetic Protein 2 / Q000008:administration & dosage* / Q000494:pharmacology; D018786:Bone Substitutes / Q000737:chemistry*; D002448:Cell Adhesion / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D008297:Male; D051379:Mice; D011092:Polyethylene Glycols / Q000737:chemistry*; D011108:Polymers; D016062:Porosity; D019736:Prostheses and Implants; D011817:Rabbits; D013499:Surface Properties; D013977:Tibia / Q000166:cytology / Q000293:injuries / Q000648:ultrastructure; D014025:Titanium / Q000737:chemistry*
chemical_list: D001577:Benzophenones; D055396:Bone Morphogenetic Protein 2; D018786:Bone Substitutes; D020099:Coated Materials, Biocompatible; D007659:Ketones; D011108:Polymers; C009495:titanium dioxide; C063834:polyetheretherketone; D011092:Polyethylene Glycols; D014025:Titanium
keywords: BMP-2; PEEK; biocompatibility; e-beam coatings; titania nanotube