School of Materials Science and Engineering, Tianjin Key Laboratory of Composite and Functional Materials, Tianjin University, Tianjin 300072, PR China.
Biomaterials. 2011 Mar;32(7):1943-9. doi: 10.1016/j.biomaterials.2010.11.019. Epub 2010 Dec 4.
We have fabricated a robust temperature sensitive hydrogel by photoinitiated copolymerization of 2-(2-methoxyethoxy)ethyl methacrylate (MeO(2)MA), 2-vinyl-4,6-diamino-1,3,5-triazine (VDT) and crosslinker polyethylene glycol diacrylate (PEGDA). It was shown that self-hydrogen bondings of VDT moieties in the bulk considerably strengthened the mechanical properties of gels, which was dependent on the weight ratio of MeO(2)/VDT and the initial monomer concentration; the VDT motifs on the surface could efficiently bind DNA for reverse gene transfection. On this soft-wet platform, gene expression lasted 7 days and the re-treated gels could be reused for new cycle of transfection. The gene modified cells could be detached by thermo-triggered switchable surface hydrophilicity of PMEO(2)MA in hydrogel. MTT assay showed low cytotoxicity of hydrogels. The results suggested that this type of mechanically strong H-bonded and thermoresponsive hydrogels hold a great potential as an integrated functional soft-wet platform for the unharmful harvest of gene modified seed cells for tissue engineering or as implantable scaffold for gene therapy and regenerative medicine applications.
我们通过 2-(2-甲氧基乙氧基)乙基甲基丙烯酸酯 (MeO(2)MA)、2-乙烯基-4,6-二氨基-1,3,5-三嗪 (VDT) 和交联剂聚乙二醇二丙烯酸酯 (PEGDA) 的光引发共聚反应，制备了一种稳健的温度敏感水凝胶。结果表明，大量 VDT 部分的自氢键在凝胶中大大增强了机械性能，这取决于 MeO(2)/VDT 的重量比和初始单体浓度；表面上的 VDT 基序可以有效地结合 DNA 用于反向基因转染。在这个柔软湿润的平台上，基因表达持续了 7 天，并且可以重新处理凝胶以进行新的转染周期。PMEO(2)MA 在水凝胶中的温度触发可切换表面亲水性可用于分离经基因修饰的细胞。MTT 分析显示水凝胶的细胞毒性低。结果表明，这种机械强度高、氢键和温度响应性的水凝胶作为一种集成的功能软湿平台，具有很大的潜力，可用于无害地收获组织工程用基因修饰种子细胞，或用作基因治疗和再生医学应用的可植入支架。
