title: Formation and bioactivity of HA nanorods on micro-arc oxidized zirconium.
abstract: A microporous and CaO partially stabilized zirconia (Ca-PSZ) coating covered with hydroxyapatite (HA) nanorods is fabricated on Zr substrate by a hybrid approach of micro-arc oxidation (MAO) and hydrothermal treatment (HT). The effect of P ions in HT solution on the density and morphology of HA was investigated; the hydrophilicity and apatite-forming ability of the Ca-PSZ coating with HA nanorods were also examined. High-density HA nanorods (with a mean diameter of 50 nm and length of 450 nm) grow on the Ca-PSZ coating after HT in a solution containing 0.002 M β-glycerophosphate disodium (β-GP). However, only a few of coarse-grained HA crystallites grow in the MAOed pores after HT in distilled water or in an ammonia aqueous solution with an initial pH value equal to the solution containing 0.002 M β-GP. P ions in the HT solution are thought to significantly promote the formation of HA nanorods. The Ca-PSZ coating covered with HA nanorods displays good hydrophilicity and excellent apatite-inducing ability, and the induced apatite prefers to nucleate on the basal-faceted surfaces of HA nanorods.
authors.affiliation: State-key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China.
authors.forename: Lan
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State-key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China.
authors.forename: Shaoyu
authors.initials: S
authors.lastname: Zhu
authors.affiliation: State-key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China. Electronic address: yonghan@mail.xjtu.edu.cn.
authors.forename: Yong
authors.initials: Y
authors.lastname: Han
authors.affiliation: State-key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, China.
authors.forename: Chengzhang
authors.initials: C
authors.lastname: Xiao
authors.affiliation: State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China.
authors.forename: Wu
authors.initials: W
authors.lastname: Tang
mesh_terms: D017886:Durapatite / Q000737:chemistry / Q000494:pharmacology*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D043942:Nanotubes; D010084:Oxidation-Reduction; D014961:X-Ray Diffraction; D015040:Zirconium / Q000737:chemistry*
chemical_list: D017886:Durapatite; D015040:Zirconium
keywords: HA nanorod; Hydrothermal treatment; Micro-arc oxidation; Zr