Polydopamine-modified metal-organic frameworks nanoparticles enhance the corrosion resistance and bioactivity of polycaprolactone coating on high-purity magnesium  

作　　者：Qingyun Fu Shaojie He Junjie Yang Ziyu Su Ping Li Xincheng Yu Weihong Jin Shulan Xu Zhentao Yu Dingsheng Zha 

机构地区：[1]Center of Oral Implantology,Stomatological Hospital,Southern Medical University,Guangzhou,China [2]Panyu Hospital of Chinese Medicine,Guangzhou 511400,China [3]Institute of Advanced Wear&Corrosion Resistant and Functional Materials,Jinan University,Guangzhou 510632,China [4]First Affiliated Hospital of Jinan University,Guangzhou 510630,China

出　　处：《Journal of Magnesium and Alloys》2024年第5期2070-2089,共20页镁合金学报（英文）

基　　金：financially supported by the Guangzhou Science and Technology Project(Nos.2021A0505030042 and 201904010060);Guangdong Basic and Applied Basic Research Foundation(No.2020B1515120078);National Natural Science Foundation of China(Nos.81401766 and 32101059);Natural Science Foundation of Guangdong Province(No.2022A1515010266);Shenzhen Key Laboratory of Musculoskeletal Tissue Reconstruction and Function Restoration and Shenzhen People’s Hospital(No.ZDSYS20200811143752005)。

摘　　要：Biodegradable magnesium(Mg)and its alloys exhibit excellent biocompatibility and mechanical compatibility,demonstrating tremendous potential for applications in orthopedics.However,the rapid degradation rate has limited their clinical application.Polycaprolactone(PCL)is commonly employed as a polymer coating to impede the rapid degradation of Mg.Unfortunately,its long-term anti-corrosion capability and bioactivity are inadequate.To address these issues,polydopamine(PDA)-modified zeolitic imidazolate framework-8(PZIF-8)bioactive nanoparticles are fabricated and incorporated into the PCL coating.The PZIF-8 particles,featuring catechol motifs,can enhance the compactness of the PCL coating,reduce its defects,and possess biomineralization ability,thereby effectively improving its anti-corrosive and bioactive properties.Moreover,the active substances released from the degradation of the PZIF-8 particles such as Zn^(2+)and PDA are beneficial for osteogenesis.The corrosion tests indicate that the corrosion current density of PCL-treated sample decreases by more than one order of magnitude and the amount of H_(2)released decreases from 0.23±0.12 to 0.08±0.08 ml cm^(-2)after doping with the PZIF-8.Furthermore,the improved corrosion resistance and released PDA and Zn^(2+)from the coating can promote osteogenic differentiation by up-regulating the expression of alkaline phosphatase activity,related osteogenic genes,and proteins.In addition,in vivo implantation experiments in rabbit femur defects further offer strong evidence that the doping of PZIF-8 nanoparticles accelerates bone reconstruction of the PCL coating.In summary,this work implies a new strategy to fabricate a PCL-based coating on Mg-based implants by introducing the PZIF-8 particles for orthopedic applications.

关 键 词：POLYDOPAMINE ZIF-8 High-purity magnesium Polycaprolactone coating ANTICORROSION Bone regeneration 

分 类 号：TG174.4[金属学及工艺—金属表面处理] R318.08[金属学及工艺—金属学]