Fabrication of silver- and strontium-doped hydroxyapatite/TiO₂ nanotube bilayer coatings for enhancing bactericidal effect and osteoinductivity

详细信息    查看全文

• 作者：Yong Huang^a ; ^b ; Xuejiao Zhang^a ; Honglei Zhang^c ; ^{zhanghl2@foxmail.com" class="auth_mail" title="E-mail the corresponding author} ; Haixia Qiao^a ; Xiaoyun Zhang^a ; Tianjun Jia^a ; ^{jianyan1@foxmail.com" class="auth_mail" title="E-mail the corresponding author} ; Shuguang Han^b ; Yuan Gao^d ; Hongyuan Xiao^e ; Hejie Yang^f
• 关键词：A. Films ; C. Corrosion ; D. Apatite ; E. Biomedical applications
• 刊名：Ceramics International
• 出版年：2017
• 出版时间：January 2017
• 年：2017
• 卷：43
• 期：1
• 页码：992-1007
• 全文大小：3251 K

文摘

Hydroxyapatite (HA)-coated implants are more susceptible to bacterial infection because their bioactive surface, which is favourable for osseointegration, could also become a reservoir for bacterial colonisation. To solve this problem, an electrodeposition method for preparing silver- and strontium-modified antibacterial HA layers onto TiO₂ nanotubes (TNs) was developed. Ag was incorporated into the HA coating to improve its antimicrobial properties. Sr was added as a second binary element to offset the potential cytotoxicity of Ag. Results showed that Sr²⁺ and Ag⁺ could be evenly incorporated into the HA lattice to form SrAgHA coatings. The TN layer with a diameter of 100 nm strengthens the adhesion via the anchoring effect. In vitro electrochemical corrosion studies demonstrated that the SrAgHA/TN coating sustains the stimulated body-fluid (SBF), thus indicating excellent corrosion resistance with a lower corrosion penetration rate than the bare commercially pure (CP)-Ti substrate. The composite coatings were found to be bioactive, based on the promotion of additional apatite onto the SrAgHA coating surface from SBF. Staphylococcus aureus growth was inhibited by SrAgHA/TN coatings, whereas the coatings without Ag had no effect on bacterial growth. MC3T3-E1 cell culture revealed that SrAgHA/TN demonstrated better cytocompatibility, and permitted stimulated cell proliferation, attachment and differentiation capacities than uncoated CP-Ti substrate. The addition of Sr to the AgHA coatings effectively counteracted the potentially negative effects and improved the performance compared with CP-Ti. The improved antibacterial effects, correlated with superior cytocompatibility and mechanical behaviour, suggested that SrAgHA/TN can be an alternative to pure HA for the preparation of reliable implant coatings for orthopaedic applications.