Preparation of soft and hard biodegradable materials for tissue engineering

1.软质材料我们设计了一种具有生物降解性和温度响应性的水凝胶，用于组织工程中的三维基质。该材料分别由两种预聚物，即带有活性羧基的IPAAm共聚物和带有聚（Ala-co-Gly）接枝链的IPAAm共聚物衍生。仅混合每种水性预聚物即可形成水凝胶，并且所得水凝胶显示出约37℃的明显体积相变温度。此外，我们证实了酶降解低于和高于转变温度。在充分溶胀的条件下，水凝胶逐渐降解。为了得到以异丙基丙烯酰胺为骨架的功能单体，我们设计合成了新型单体。这些是2-羟基异丙基丙烯酰胺，N，N-二甲基氨基异丙基丙烯酰胺。包含IPAAm和这些单体的共聚物将有效地调节IPAAm的分子量。 关于我们 2.硬质材料为了获得硬质的可生物降解材料，并易于设计所需的形状，我们制备了光交联聚（ε-己内酯-co-丙交酯）。实际上，诸如熔点（软化点）的热性质密切取决于交联材料中己内酯和丙交酯的组成。我们使用模型细胞，常规培养的HeLa细胞，检查了制备的膜状材料上的细胞粘附。有趣的是，细胞粘附和生长依赖于己内酯和丙交酯的组成。其生长速率与组织培养聚苯乙烯（TCPS）相当，有时甚至更好。我们还研究了蛋白质吸附的交联材料使用模型蛋白，白蛋白和牛血清。结果表明，蛋白质的粘附能力强于细胞的粘附和生长能力强的材料，从而成功地制备了两种可用于组织工程的高分子材料，即酶降解水凝胶和交联聚己内酯-丙交酯材料。少

1.Soft MaterialsWe designed the hydrogel which has biodegradability and a temperature response for the three-dimensional matrix in tissue engineering. The materials was derived from two kinds of prepolymer, that is, IPAAm copolymer with activated carboxyl groups and one with poly(Ala-co-Gly) grafted chains, respectively. Only mixing of each aqueous prepolymer instanlt formed hydrogel and resulting one showed a clear volume phase transition temperature around 37℃. Moreover, we confirmed the enzymatic degradation below and above the transition temperature. In the well-swelled condition, the hydrogel was degraded gradually. This result suggested the hydrogel would be used for three-dimensional cell culture system.To obtain the functional monomer with isopropylacrylamide backbone, we designed and synthesized new type of monomers. These are 2-hydroxyisopropylacrylamide, N,N-dimthylaminoisopropylacrylamide. The copolymer comprising IPAAm and these monomers would be effective to modulate the … More transition temperature or to improve the cell ineraction with the synthesized matrix.2.Hard MaterialsTo obtain the hard biodegradable materials with easiness to design the desirable shape, we prepared the light-cross-linkable poly(ε-caprolactone-co-lactide). Actually, thermal propertied such as the melting points (softening points) closely depended on the composition of the caprolactone and the lactide in the cross-linked materials. We checked the cell adhesion on the prepared membrane-shaped materials using the model cell, conventionally cultured HeLa cell. Interestingly, the cell adhesion and growth depended on the composition of the caprolactone and the lactide. The rate of the growth is comparable to that of the tissue culture polystyrene (TCPS) or sometimes better. We also investigated the protein adsorption on the cross-linked materials using model protein, albumin and bovine serum. From the results, More protein adhered on the the materials that showed more cell adhesion and growth.From these projects, we succeeded the two types of the polymeric materials, such as enzymatically degradable hydrogels and cross-linked poly(ε-caprolactone-co-lactide) and these are useful for the tissue engineering. Less