摘要
背景:聚乳酸具有良好的生物相容性和生物降解性,成为一种新型的骨科固定材料,然而该材料缺乏细胞识别信号,不利于细胞黏附和成骨分化,限制了其在生物材料中的应用。目的:3D打印聚乳酸-纳米羟基磷灰石/壳聚糖支架,评估其药物缓释及生物性能。方法:采用熔融沉积技术打印孔隙交互的多孔聚乳酸支架(记为PLA支架),将该支架浸泡于多巴胺溶液中制备聚乳酸-多巴胺支架(记为PLA-DA支架);将纳米羟基磷灰石投入壳聚糖溶液中,然后将PLA-DA支架浸没其中,制备聚乳酸-纳米羟基磷灰石/壳聚糖支架(记为PLA-nHA/CS支架),表征3组支架的微观形貌、孔隙率、水接触角与压缩强度。采用冷冻干燥法制备负载药物多西环素的PLA-nHA/CS支架(记为PLA-nHA/CS-DOX支架),表征其药物释放。将PLA、PLA-DA、PLA-nHA/CS、PLA-nHA/CS-DOX支架分别与MC3T3-E1细胞共培养,检测细胞增殖与成骨分化能力;将不同浓度的金黄色葡萄球菌悬液分别与4组支架共培养,采用抑菌圈实验检测支架的抗菌性能。结果与结论:①扫描电镜下可见PLA、PLA-DA支架表面致密光滑,PLA-nHA/CS支架表面可见纳米羟基磷灰石颗粒;PLA、PLA-DA、PLA-nHA/CS支架的孔隙率逐渐降低,压缩强度逐渐升高,PLA-nHA/CS支架的弹性模量满足松质骨要求;PLA-DA、PLA-nHA/CS支架的水接触角小于PLA支架;PLA-nHA/CS支架体外可持续释放药物达8 d。②CCK-8检测显示,4组支架均未显著影响MC3T3-E1细胞的增殖;PLA-DA组、PLAnHA/CS组、PLA-nHA/CS-DOX组细胞碱性磷酸酶活性均高于PLA组;茜素红染色显示,与PLA组相比,PLA-nHA/CS组、PLA-nHA/CS-DOX组细胞表现出较高的矿化水平。③抑菌圈实验显示PLA、PLA-DA支架无抗菌性能,PLA-nHA/CS支架具有一定的抗菌性能,PLA-nHA/CS-DOX支架具有超强的抗菌性能。④结果表明,PLA-nHA/CS-DOX支架具有良好的药物缓释性能、细胞相容性、促成骨性能及抗菌性能。
BACKGROUND:Polylactic acid has good biocompatibility and biodegradability,and has become a new orthopedic fixation material.However,the lack of cell recognition signal of this material is not conducive to cell adhesion and osteogenic differentiation,which limits its application in biomaterials.OBJECTIVE:3D-printed polylactic acid-nano-hydroxyapatite(nHA)/chitosan(CS)scaffold to evaluate its drug sustained-release and biological properties.METHODS:The porous polylactic acid scaffold(recorded as PLA scaffold)with interporous pores was printed by fused deposition modeling technique,and the scaffold was soaked in dopamine solution to prepare polylactic acid-dopamine scaffold(recorded as PLA-DA scaffold).Nano-hydroxyapatite was immersed in chitosan solution,and then the PLA-DA scaffold was immersed in it to prepare polylactic acid-nano-hydroxyapatite/chitosan scaffold(recorded as PLA-nHA/CS scaffold).The micro-morphology,porosity,water contact angle,and compressive strength of the three scaffolds were characterized.PLA-nHA/CS scaffold loaded with doxycycline(recorded as PLA-nHA/CS-DOX scaffold)was prepared by freeze-drying method,and its drug release was characterized.PLA,PLA-DA,PLA-nHA/CS,and PLA-nHA/CS-DOX scaffolds were co-cultured with MC3T3-E1 cells,separately,to detect cell proliferation and osteogenic differentiation.Staphylococcus aureus suspensions of different concentrations were co-cultured with four groups of scaffolds.The antibacterial performance of scaffolds was detected by inhibition zone test.RESULTS AND CONCLUSION:(1)Under scanning electron microscopy,the surfaces of PLA and PLA-DA scaffolders were dense and smooth,and nHA particles were observed on PLA-nHA/CS scaffolders.The porosity of PLA,PLA-DA and PLA-nHA/CS scaffolds decreased gradually,and the compressive strength increased gradually.The elastic modulus of PLA-nHA/CS scaffolds met the requirements of cancelous bone.The water contact angle of PLA-DA and PLA-nHA/CS brackets was smaller than that of PLA scaffolds.The PLA-nHA/CS scaffold sustainably released drugs in vitro for 8 days.(2)CCK-8 assay showed that the proliferation of MC3T3-E1 cells was not significantly affected by the four groups of scaffolds.The activity of alkaline phosphatase in PLA-DA group,PLA-nHA/CS group,and PLA-nHA/CS-DOX group was higher than that in PLA group.Alizarin red staining showed that compared with PLA group,the cells in PLA-nHA/CS group and PLA-nHA/CS-DOX group showed higher mineralized water level.(3)Inhibition zone test exhibited that PLA and PLA-DA scaffolds had no antibacterial properties.PLA-nHA/CS scaffolds had certain antibacterial properties.PLA-nHA/CS-DOX scaffolds had super antibacterial properties.(4)The results showed that the PLA-nHA/CS-DOX scaffold had good drug release performance,cell compatibility,osteogenic properties,and antibacterial properties.
作者
刘岩
郑雪新
Liu Yan;Zheng Xuexin(Department of Scientific Research,Fuzhou Second Hospital,Fuzhou 350007,Fujian Province,China)
出处
《中国组织工程研究》
CAS
北大核心
2024年第22期3532-3538,共7页
Chinese Journal of Tissue Engineering Research
基金
福建省卫生健康科研人才培养项目(2019-2-27),项目负责人:刘岩
福建省创伤骨科急救与康复临床医学研究中心项目(2020Y2014)
关键词
3D打印
聚乳酸支架
纳米羟基磷灰石
多巴胺
壳聚糖
抗菌涂层
药物缓释
骨再生
3D printing
polylactic acid scaffold
nano-hydroxyapatite
dopamine
chitosan
antibacterial coating
drug sustained release
bone regeneration
