Injectable, High Porosity Bone Scaffolds by Emulsion Templating

描述（由申请人提供）：生物材料支架的细胞过程、生物降解和机械性能的控制在组织工程器械的开发中至关重要。人们普遍认为，脚手架建筑，特别是可以深刻地影响建设的成功。骨组织工程策略的进展强烈依赖于能够承受严格体内负荷的高孔隙率支架的开发。拟议的研究利用乳液模板生成新的微孔聚合物作为可注射的，可生物降解的骨再生支架。乳液模板法是一种相对较新的制备高度多孔支架的方法，涉及高内相乳液（HIPE）的模板聚合。通过乳液模板提供的支架结构的控制使得聚HIPE材料成为组织工程支架的有吸引力的候选者。此外，HIPE可以在没有溶剂的情况下制备，具有允许注射性的乳液粘度，并且在体温或体温附近固化。我们建议调整乳液组装过程，以产生具有改善的机械性能和目标降解曲线的聚HIPE结构。我们假设这些支架的高孔隙率和互连性将通过促进细胞向内生长、营养物质的流入和废物在整个支架中的运输来增强组织再生。具体目的是：1）开发和表征具有互连孔隙率的可注射聚HIPE支架库。2)评价目标1中开发的聚HIPE支架作为骨传导组织工程支架。 这些目标的成功完成将产生既可生物降解又可注射的高孔隙率支架。可注射并原位固化至合适机械强度的高度多孔支架代表了骨科组织工程的重大进步。这种创新的制造设计还提供了对架构的特殊控制，可用于探测组织再生中的关键关系。尽管这些研究集中在骨修复上，但乳液模板可用于生成各种功能性移植物。 公共卫生相关性：全国住院病人统计数据显示，仅2004年就进行了110多万例手术，包括部分切除骨、骨移植和住院骨折修复，估计总费用超过50亿美元。当传统的移植无法获得或失败时，工程组织移植物具有修复受损组织的潜力。该研究利用乳液模板生成可注射的可生物降解支架，用于修复骨缺损。

DESCRIPTION (provided by applicant): Control of cellular processes, biodegradation and mechanical properties of biomaterial scaffolds is critical in the development of tissue engineering devices. It is widely recognized that scaffold architecture, in particular, can profoundly influence the success of the construct. The advancement of bone tissue engineering strategies is strongly dependent on the development of high-porosity scaffolds that can withstand rigorous in vivo loading. The proposed research utilizes emulsion templating to generate novel microcellular polymers as injectable, biodegradable scaffolds for bone regeneration. Emulsion templating is a relatively new method for the production of highly porous scaffolds and involves the template polymerization of high internal phase emulsions (HIPEs). The control of scaffold architecture afforded by emulsion templating makes polyHIPE materials attractive candidates for tissue engineering scaffolds. In addition, HIPEs can be made without solvent, have an emulsion viscosity that permits injectability, and cure at or around body temperature. We propose to tune the emulsion assembly processes to generate polyHIPE architectures with improved mechanical properties and target degradation profiles. We hypothesize that the high porosity and interconnectivity of these scaffolds will augment tissue regeneration by facilitating cellular in-growth, the influx of nutrients and the transport of waste throughout the scaffold. The Specific Aims are: 1) Develop and characterize a library of injectable polyHIPE scaffolds with interconnected porosity. 2) Evaluate polyHIPE scaffolds developed in Aim 1 as osteoconductive tissue engineering scaffolds. Successful completion of these Aims will generate high porosity scaffolds that are both biodegradable and injectable. A highly porous scaffold that is injectable and cures in situ to suitable mechanical strength represents a significant advancement in orthopaedic tissue engineering. This innovative fabrication design also provides exceptional control over the architecture which can be utilized to probe key relationships in tissue regeneration. Although these studies are focused on bone repair, emulsion templating can be utilized to generate a wide variety of functional grafts. PUBLIC HEALTH RELEVANCE: Nationwide Inpatient Statistics show that over 1.1 million surgical procedures involving the partial excision of bone, bone grafting, and inpatient fracture repair were performed in 2004 alone, with an estimated total cost of over $5 billion. Engineered tissue grafts have the potential to repair damaged tissues when traditional transplants are unavailable or fail. The proposed research utilizes emulsion templating to generate injectable, biodegradable scaffolds for the repair of bone defects.