title: Osteoblast proliferation on hydroxyapatite coated substrates prepared by right angle magnetron sputtering.
abstract: The preparation of hydroxyapatite (HA) coatings via a versatile right-angle magnetron sputtering (RAMS) approach for use as a biomaterial has recently been reported. RAMS coatings show some advantages over conventionally sputtered films in that room temperature deposition yields nanocrystalline and nearly stoichiometric HA coatings under appropriate conditions, thereby avoiding the troublesome post deposition annealing treatment. In this article, we present an exploratory study of the biocompatibility of RAMS HA coatings deposited on metallic substrates. RAMS HA coatings with a thickness around 500nm were prepared on various substrates. X-ray diffraction (XRD) analysis showed that the as-deposited HA coatings were polycrystalline with some strongly preferred orientations. Atomic force microscopy (AFM) results showed that the coatings were rather smooth with surface roughness on the order of 10 nm. X-ray photoelectron spectroscopy (XPS) confirmed that the surface chemistry was nearly stoichiometric. To study the biocompatibility of these coatings, murine pre-osteoblastic MC3T3-E1 cells were seeded onto various substrates. Cell density counts using fluorescence microscopy showed that the best osteoblast proliferation is achieved on an HA RAMS-coated titanium substrate. Additionally, in preliminary studies the influence of Zn, Mg, and Al incorporation in the HA crystal lattice on the in vitro behavior was also evaluated. These experiments demonstrate that RAMS is a promising coating technique for biomedical applications.
authors.affiliation: Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, USA. z.hong.nu@gmail.com
authors.forename: Zhendong
authors.initials: Z
authors.lastname: Hong
authors.forename: Alexandre
authors.initials: A
authors.lastname: Mello
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Yoshida
authors.forename: Lan
authors.initials: L
authors.lastname: Luan
authors.forename: Paula H
authors.initials: PH
authors.lastname: Stern
authors.forename: Alexandre
authors.initials: A
authors.lastname: Rossi
authors.forename: Don E
authors.initials: DE
authors.lastname: Ellis
authors.forename: John B
authors.initials: JB
authors.lastname: Ketterson
mesh_terms: D000535:Aluminum / Q000494:pharmacology; D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000494:pharmacology*; D017886:Durapatite / Q000494:pharmacology*; D005453:Fluorescence; D008274:Magnesium / Q000494:pharmacology; D008422:Materials Testing / Q000379:methods*; D051379:Mice; D018625:Microscopy, Atomic Force; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects*; D056951:Photoelectron Spectroscopy; D014025:Titanium / Q000494:pharmacology; D014961:X-Ray Diffraction; D015032:Zinc / Q000494:pharmacology
chemical_list: D020099:Coated Materials, Biocompatible; D017886:Durapatite; D000535:Aluminum; D014025:Titanium; D008274:Magnesium; D015032:Zinc