脂质体介导温敏型海藻酸/磷酸三钙/胶原Ⅰ水凝胶的性能  

Properties of a liposomes-mediated thermo-sensitive alginate/alpha-tricalcium phosphate/collagen Ⅰ composite hydrogel

作　　者：谢宜刚 李小丽[3] 陈昌盛[3] 廖振华[3] 刘伟强[1,3] Xie Yi-gang;Li Xiao-li;Chen Chang-sheng;Liao Zhen-hua;Liu Wei-qiang(Department of Biomedical Engineering, Tsinghua University, Beijing 100084, China;Department of Biomedical Engineering, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong Province, China;Key Laboratory of Biomedical Materials and Implant Devices, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057, Guangdong Province, China)

机构地区：[1]清华大学生物医学工程系,北京市100084 [2]清华大学深圳研究生院生物医学工程系,广东省深圳市518055 [3]深圳清华大学研究院生物医用材料及植入器械重点实验室,广东省深圳市518057

出　　处：《中国组织工程研究》2018年第14期2197-2202,共6页Chinese Journal of Tissue Engineering Research

基　　金：国家自然科学基金(51403116);广东省自然科学基金(2015A030313698)~~

摘　　要：背景:温敏水凝胶具有仿细胞外基质、良好生物相容性、微创可注射和原位成型等特点,在组织工程中广泛使用。目的:制备脂质体介导的温敏型海藻酸/磷酸三钙/胶原Ⅰ(Alg/TCP/Col)水凝胶,并对其进行表征。方法:通过交错融合制备包载不同浓度钙离子的脂质体Ca-IFVs,综合考察脂质体包封率和载药率,筛选最佳钙离子浓度的脂质体,用于以下实验。将Alg/TCP/Col前体溶液(海藻酸或海藻酸/磷酸三钙前体溶液)与脂质体Ca-IFVs以不同的配比(5,10,15,20)在37℃下混合,制备温敏型水凝胶,观察水凝胶的结构、流变性、体积溶胀比及机械性能。将MC3T3-E1细胞分别接种于Alg/TCP/Col水凝胶、海藻酸水凝胶、海藻酸/磷酸三钙水凝胶表面,接种1,3,7 d后,采用共聚焦显微镜观察细胞形态。结果与结论:(1)冻干水凝胶中孔的尺寸在50-100μm范围,α-磷酸三钙的颗粒均匀地附着在海藻酸/α-磷酸三钙水凝胶的表面上;与海藻酸/α-磷酸三钙水凝胶相比,Alg/TCP/Col水凝胶是具有胶原纤维的致密聚集体;(2)Alg/TCP/Col水凝胶具有在35-39℃之间适当的相转变温度Tm;(3)随着复合材料凝胶中Ca-IFVs体积的增加,凝胶体积溶胀比增加,当将α-磷酸三钙复合物加入到海藻酸/α-磷酸三钙水凝胶中时,溶胀比略有降低;与海藻酸/α-磷酸三钙水凝胶相比,Alg/TCP/Col水凝胶的溶胀比增加;(4)在前体溶液与脂质体配比为10时,Alg/TCP/Col水凝胶、海藻酸/α-磷酸三钙水凝胶的压缩模量高于海藻酸水凝胶(P<0.05);(5)在前体溶液与脂质体配比为10时,海藻酸水凝胶表面的MC3T3-E1细胞呈圆形;海藻酸/α-磷酸三钙水凝胶中的细胞形态趋于扩展,散布在水凝胶孔表面上;在Alg/TCP/Col水凝胶表面的细胞具有应力延长形态,细胞形态趋势相似,并向凝胶内部延伸,同时数量显著增加;(6)结果表明脂质体介导的Alg/TCP/Col水凝胶,具有良好的机械性能及细胞相容性。BACKGROUND： The thermo-sensitive composite hydrogels have gained increasing interest in bone regeneration domain due to their biomimetic extracellular matrix（ECM） structure, good biocompatibility, minimal invasive performance and in situ molding. OBJECTIVE： To prepare a thermo-sensitive injectable alginate/α-tricalcium phosphate（α-TCP）/collagen I（Alg/TCP/Col） composite hydrogel and explore its characterization. METHODS： Ca-carrying interdigitation-fusion vesicles（Ca-IFVs） were prepared. The liposomes carrying the optimal concentration of calcium ions were selected for the following experiments by investigating their encapsulation efficiency and drug loading rate. Alg/TCP/Col precursor solution（Alg or Alg/TCP precursor solution） was mixed with Ca-IFVs at 37 ℃ in different proportions（5, 10, 15, 20） to prepare thermosensitive hydrogels. The structure, rheology behavior, volume swelling ratio, and mechanical properties of the composite hydrogel were observed. MC3 T3-E1 cells were co-cultured with Alg/TCP/Col, Alg, and Alg/TCP hydrogels, respectively. Then, morphology of the cells was observed by confocal microscopy at 1, 3, 7 days after co-culture. RESULTS AND CONCLUSION：（1） The pore size of the freeze-dried hydrogel was 50-100 μm, and TCP particles uniformly adhered to the surface of the Alg/TCP hydrogel surface. The Alg/TCP/Col hydrogel was a dense aggregate with collagen fibers in contrast to the Alg/TCP hydrogel.（2） The Alg/TCP/Col hydrogel exhibited a suitable phase transition temperature（Tm） between 35-39 ℃.（3） The volume swelling ratio of the hydrogel was increased with the increase of Ca-IFVs size. When the α-TCP complex was added into the Alg/TCP hydrogel, the swelling ratio decreased slightly. Alg/TCP/Col hydrogel exhibited a higher swelling ratio than the Alg/TCP hydrogel.（4） When the mixture ratio of precursor solution to liposome was 10, the compressive modulus of Alg/TCP/Col hydrogel and Alg/TCP hydrogel was significantly higher than that of t

关 键 词：水凝胶 胶原 脂质体 磷酸钙类 组织工程 组织修复 温度敏感 国家自然科学基金 生物材料 

分 类 号：R318[医药卫生—生物医学工程]