Application of Copolymers of Lactic Acid and Amino Acid Having Reactive Side-Chain Groups as Biodegradable Materials for Tissue Engineering

在与损伤或丢失的组织再生相关的组织工程中，人们希望使用性能优良的生物可降解材料作为临时支架，以支持细胞生长，并随着组织再生的进行而消失。我们以前合成了具有反应性侧链基团的可生物降解的聚(去脂肽-随机-丙交酯)、聚[(GLC-Asp)-r-LA]和聚[(GLC-Lys)-r-LA]。在这项研究中，为了评价这些共聚物作为组织再生功能支架的有效性，使用含有不同数量的羧基或氨基的共聚物膜，研究了反应性侧链和离子侧链对细胞附着和生长的影响。具有适当正负电荷的聚[(Glc-Lys)-r-LA]和聚[(Glc-Asp)-r-LA]薄膜比聚L-丙交酯具有更强的细胞黏附能力。在共聚物膜上观察到细胞生长良好。在细胞培养过程中，共聚物膜表现出较高的降解率，其降解率与去脂肽单元含量有关。利用含有不同量去脂肽单元的共聚物，成功地制备了具有活性表面和可控降解性的可生物降解的细胞生长聚合物基质。此外，为了评价这些共聚体作为组织再生功能支架的有效性，采用冷冻干燥法制备了三维多孔海绵，并用不同含量的羧基或氨基的共聚海绵研究了反应性侧链和离子侧链对细胞生长和降解行为的影响。细胞在共聚海绵上生长良好。在细胞培养过程中，共聚物海绵的降解率与脱脂多肽单位含量有关。利用这些共聚物成功地制备了表面活性好、降解行为可控、细胞生长良好的三维可生物降解聚合物基质。这类共聚物基质是组织工程支架的理想候选材料。

In tissue engineering related to the regeneration of damaged or lost tissue, excellent biodegradable materials are desired as temporary scaffolds to support cell growth and disappear with the progress of tissue regeneration. We previously synthesized biodegradable poly(depsipeptide-random-lactide), poly[(Glc-Asp)-r-LA] and poly[(Glc-Lys)-r-LA] having reactive side-chain groups. In this study, to evaluate the utility of these copolymers as functional scaffolds for tissue regeneration, the effects of reactive and ionic side-chain groups on cell attachment and growth were investigated using copolymer films with various amounts of carboxyl or amino groups. Poly[(Glc-Lys)-r-LA] and poly[(Glc-Asp)-r-LA] films having appropriate positive or negative charges exhibited higher cell attachment ability than poly-L-lactide. Good cell growth was observed on the copolymer films. During cell culture, the copolymer films exhibited higher degradation rates related to the depsipeptide unit content. Biodegradable polymer matrices for cell growth, with reactive surfaces and controllable degradability, were successfully prepared using copolymers with various amounts of depsipeptide units. Moreover, to evaluate the utility of these copolyrners as functional scaffolds for tissue regeneration, three-dimensional porous sponges were prepared by freeze-drying method and the effects of reactive and ionic side-chain groups on cell growth and degradation behavior were investigated using copolymer sponges with various amounts of carboxyl or amino groups. Good cell growth was observed on the copolymer sponges. During cell culture, the copolymer sponges exhibited various degradation rates related to the depsipeptide unit content. Three-dimensional biodegradable polymer matrices with reactive surface, controllable degradation behavior and good cell growth were successfully prepared using these copolymers. Such kinds of copolymer matrices are good candidate for scaffold for tissue engineering.