Novel Biodegradable Materials for Tissue Engineering

近年来，生物材料工程的重点已经从生物稳定材料转向可生物降解材料 在生理条件下可降解为无毒产品的材料。乳酸和聚乳酸的聚合物 乙醇酸及其共聚物聚(丙交酯-乙交酯)(Plaga)是一些最常用的 医用可生物降解聚合物。所有这些聚合物都有一定的局限性， 这就要求寻找具有生物相容性和生物响应性的新型可生物降解材料。 生物降解聚磷腈是近年来发展起来的一类独特的无机聚合物，具有潜在的应用前景。 由于其前所未有的合成能力，成为各种生物医学应用的理想候选者 灵活性和多功能性。PI之前已经证明了聚磷腈与Plaga的混合 可显著阻止Plaga和相关的酸性降解产物的积累 炎症反应，同时可以显著改善其机械性能和 骨传导性。我们相信，聚磷腈的合成灵活性将使新颖的设计成为可能 大分子，可与Plaga进行可混溶共混，提高生物活性。这些小说 由于其良好的生物降解性、力学和生物性能结合在一起 骨性完整性可以满足骨科的各种需求。这一目标将通过以下方式实现 具体目标：具体目标1：设计、合成和表征新型可生物降解材料 聚磷腈可与Plaga形成可混溶的共混物作为骨组织的候选材料 工程学。具体目标2：构建聚磷腈与Plaga的新型共混物并执行 对这些混合物的优化研究侧重于物理化学性质的改善， 力学性能、体外降解、体外矿化和骨传导性。具体目标3： 使用活体动物模型对聚磷腈与Plaga的新型混合物进行生物学评估。

In recent years emphasis in biomaterial engineering has shifted from biostable materials to biodegradable materials that can degrade to non-toxic products under physiological conditions. Polymers of lactic and glycolic acid and their copolymers poly(lactide-co-glycolide), (PLAGA) are some of the most commonly used biodegradable polymers for medical applications. All these polymers are associated with some limitations, which demand the search for novel biodegradable materials that are biocompatible and bioresponsive. Biodegradable polyphosphazenes, a unique class of inorganic polymer developed recently have the potential to become ideal candidates for various biomedical applications due to their unprecedented synthetic flexibility and versatile properties. PI had previously shown that blending polyphosphazenes with PLAGA can significantly preclude the accumulation of acidic degradation products of PLAGA and associated inflammatory reponses, at the same time can significantly improve their mechanical properties and osteoconductivity. We believe that the synthetic flexibility of polyphosphazenes will allow the design of novel macromolecules, which can for miscible blends with PLAGA and increase the bioactivity. These novel blends due to their well-tuned biodegradability, mechanical and biological properties combined with osteointegrity can serve a variety of needs in orthopaedics. This goal will be achieved via the following specific aims: Specific Aim 1: To design, synthesize and characterize novel biodegradable polyphosphazenes, which can form miscible blends with PLAGA as candidate materials for bone tissue engineering. Specific Aim 2: To construct novel blends of polyphosphazenes with PLAGA and perform optimization studues with these blends focusing on improvements in physico-chemical properties, mechanical properties, in vitro degradation, in vitro mineralization and osteoconductivity. Specific Aim 3: To perform biological evaluation of novel blends of polyphosphazenes with PLAGA using in vivo animal models.