title: Spatially-controlled distribution of HACC in mineralized collagen coatings for improving rhBMP-2 loading and release behavior.
abstract: In this study, mineralized collagen (COL) coatings with controlled loading and release of bone morphogenetic protein (rhBMP-2) as well as enhanced osteogenic differentiation were successfully achieved via the spatially-control of hydroxypropyltrimethyl ammonium chloride chitosan (HACC) within the coatings. The distribution of HACC in the inner part (HACC-IN) or the outer part (HACC-OUT) of the coatings were adjusted by different potential values and negative/positive alternations during alternating potentials assisted electrochemical deposition (AP-ECD). It was found that rhBMP-2 loading capacity was remarkably enhanced with the increased incorporation of HACC due to their strong interaction, and the release behavior was also tuned by HACC location. In general, HACC-IN coatings showed a prominent improvement in cytocompatibility and osteogenic differentiation. The main reason is considered that the inner location of HACC can eliminate the negative effect of HACC to initial cellular adhesion and bring to a sustained rhBMP-2 release behavior due to kinetic modification. An optimized coating in this work could load as high as 4644ng/cm(2) rhBMP-2 and release only 25% for 14 days, which consequently leads to a better osteogenic differentiation. This study has thus inspired another promising protocol for designing growth factor incorporated bioactive coatings for bone implants with improved osteointegration.
authors.affiliation: School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027, China.
authors.forename: Lu
authors.initials: L
authors.lastname: Chen
authors.affiliation: The First Affiliated Hospital of Medical College, Zhejiang University, Hangzhou 310003, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Lin
authors.affiliation: The First Affiliated Hospital of Medical College, Zhejiang University, Hangzhou 310003, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.affiliation: School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027, China.
authors.forename: Xiaozhao
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027, China.
authors.forename: Junjun
authors.initials: J
authors.lastname: Zhuang
authors.affiliation: The First Affiliated Hospital of Medical College, Zhejiang University, Hangzhou 310003, China.
authors.forename: Huiming
authors.initials: H
authors.lastname: Wang
authors.affiliation: School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027, China. Electronic address: chengkui@zju.edu.cn.
authors.forename: Kui
authors.initials: K
authors.lastname: Cheng
authors.affiliation: School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027, China. Electronic address: wengwj@zju.edu.cn.
authors.forename: Wenjian
authors.initials: W
authors.lastname: Weng
mesh_terms: D055396:Bone Morphogenetic Protein 2 / Q000737:chemistry*; D048271:Chitosan / Q000031:analogs & derivatives* / Q000737:chemistry; D003094:Collagen / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*
chemical_list: D055396:Bone Morphogenetic Protein 2; D000644:Quaternary Ammonium Compounds; C576941:hydroxypropyltrimethyl ammonium chloride chitosan; D003094:Collagen; D048271:Chitosan
keywords: Cytocompatibility; Electrochemical deposition; HACC location; Mineralized collagen coating; rhBMP-2 loading