Self Healing Biomaterials

描述(由申请人提供)：在生物材料中，机械故障的原位修复仍然是一个很大程度上未经检验的研究领域。材料科学的一个新兴领域是“自修复材料”(SHM)，它使用各种嵌入的化学物质在微裂纹结合成扩展裂纹之前在原位检测和修复微裂纹。这份R21提案研究了将生物兼容、无毒的SHM技术融入最简单的承重生物材料配方之一--双组分丙烯酸骨水泥--和最直接的SHM技术--分散在催化剂嵌入聚合物基质中的微胶囊修复剂中的可行性。这项研究包括四个具体目标。目的1：采用乳化油包水界面聚合法制备微胶囊氰基丙烯酸酯类医疗剂。目的2：将微胶囊化的愈合剂掺入双组分PMMA基质中。目的3：表征自愈骨水泥的力学性能和断裂力学。目的：通过小鼠成纤维细胞培养中提取液的放散试验和人成骨细胞培养中骨水泥样品上的细胞生长试验来检测自愈骨水泥的细胞毒性。 与公共卫生相关：所有循环加载的生物材料最有可能的失效模式是由微裂纹积累引起的疲劳失效。这项研究的长期目标是开发能够修复微裂纹水平上的故障的复合生物材料，从而延长循环加载生物材料的使用寿命。本项目专门测试了以丙烯酸骨水泥作为生物材料模型的概念可行性。

DESCRIPTION (provided by applicant): In situ repair of mechanical failure remains a largely unexamined area of study in biomaterials. A newly emerging area of materials science is "Self-Healing Materials" (SHM) that uses a variety of embedded chemistries to detect and repair microcracks in situ before they coalesce into propagating cracks. This R21 proposal examines the feasibility of incorporating biocompatible, non-toxic SHM technology into one of the simplest load-bearing biomaterial formulations -- two component acrylic bone cement -- with the most straightforward SHM technology -- microencapsulated healing agent dispersed in a catalyst-embedded polymer matrix. The study consists of four specific aims. Aim 1: Fabrication of microencapsulated alkyl cyanoacrylate healing agent using emulsified oil in water interfacial polymerization. Aim 2: Incorporation of the icroencapsulated healing agent into the two-component PMMA matrix. Aim 3: Characterization of self-healing bone cement mechanical properties and fracture mechanics. Aim 4: Cytotoxicity testing of self-healing bone cement by elution testing of extraction media in mouse fibroblast culture, and by cell ongrowth onto samples of bone cement placed in cultures of human osteoblasts. PUBLIC HEALTH RELEVANCE: The most likely mode of failure of all cyclically loaded biomaterials is fatigue failure resulting from the accumulation of microcracks. The long-term goal of this study is to develop composite biomaterials that have the capacity to repair failure at the microcrack level and thus prolong the use life of cyclically loaded biomaterials. This project specifically tests out the concept feasibility using acrylic bone cement as a model biomaterial.