title: Preparation and characterization of TiO2/silicate hierarchical coating on titanium surface for biomedical applications.
abstract: In the current work, TiO2/silicate hierarchical coatings with various nanostructure morphologies were successfully prepared on titanium substrates through micro-arc oxidation (MAO) and subsequent hydrothermal treatment (HT). Moreover, the nucleation mechanism and growth behavior of the nanostructures, hydrophilicity, protein adsorption and apatite-inducing ability of various coatings were also explored. The novel TiO2/silicate hierarchical coatings comprised calcium silicate hydrate (CSH) as an outer-layer and TiO2 matrix as an inner-layer. According to the morphological features, the nanostructures were classified as nanorod, nanoplate and nanoleaf. The morphology, degree of crystallinity and crystalline phases of CSH nanostructures could be controlled by optimizing the HT conditions. The nucleation of CSH nanostructures is caused by release and re-precipitation mechanism. The TiO2/CSH hierarchical coatings exhibited some enhanced physical and biological performances compared to MAO-fabricated coating. The improvement of the hydrophilicity, fibronectin adsorption and apatite-inducing ability was found to be morphological dependent according to the following trend: nanoleaf coating>nanoplate coating>nanorod coating>MAO coating. The results indicate that the tuning of physical and morphological properties of nanostructures coated on biomaterial surface could significantly influence the hydrophilicity, protein adsorption and in vitro bioactivity of biomaterial.
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Qianli
authors.initials: Q
authors.lastname: Huang
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China; Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, China.
authors.forename: Xujie
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China; Biomaterials Department, Inorganic Chemical Industries Division, National Research Centre, Dokki, 12622 Cairo, Egypt.
authors.forename: Tarek A
authors.initials: TA
authors.lastname: Elkhooly
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Ranran
authors.initials: R
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Yang
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Zhijian
authors.initials: Z
authors.lastname: Shen
authors.affiliation: State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China; Key Laboratory of Advanced Materials of Ministry of Education of China, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China. Electronic address: biomater@mail.tsinghua.edu.cn.
authors.forename: Qingling
authors.initials: Q
authors.lastname: Feng
mesh_terms: D017610:Calcium Compounds / Q000737:chemistry; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D017610:Calcium Compounds; D020099:Coated Materials, Biocompatible; D017640:Silicates; C009495:titanium dioxide; D014025:Titanium; C031293:calcium silicate
keywords: Calcium silicate hydrate; Hydrothermal treatment; Micro-arc oxidation; Surface chemistry; Surface topography; Titanium implant