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设备的开发中至关重要。人们普遍认为，脚手架建筑，尤其是脚手架建筑，可以深刻地影响建筑的成功。骨组织工程策略的进步很大程度上依赖于高孔率支架的开发，这种支架能够承受严格的活体载荷。这项拟议的研究利用乳液模板来产生新型微孔聚合物，作为可注射的、可生物降解的骨再生支架。乳液模板是一种相对较新的制备高孔支架的方法，涉及到高内相乳液(HIPE)的模板聚合。乳液模板对支架结构的控制使聚HIPE材料成为组织工程支架的候选材料。此外，HIPE可以在不含溶剂的情况下制成，具有允许注射的乳液粘度，并在体温或体温附近固化。我们建议调整乳液组装过程，以生成具有更好的机械性能和目标降解轮廓的聚HIPE结构。我们推测，这些支架的高孔隙率和互连性将通过促进细胞内生长、营养物质的流入和废物在支架中的运输来增强组织再生。具体目标是：1)开发和表征具有相互连接的孔隙率的可注射聚HIPE支架的库。2)评价AIM 1中开发的聚HIPE支架作为骨传导组织工程支架。这些目标的成功实现将产生既可生物降解又可注射的高孔隙率支架。一种高度多孔的支架，可以注射并原位固化到合适的机械强度，代表着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，可用于探索组织再生中的关键关系。虽然这些研究主要集中在骨修复上，但乳胶模板可以用于产生各种各样的功能移植物。 公共卫生相关性：全国住院患者统计数据显示，仅在2004年，就进行了超过110万例涉及部分切除骨、骨移植和住院骨折修复的外科手术，估计总成本超过50亿美元。当传统移植无法获得或失败时，工程化组织移植具有修复受损组织的潜力。这项拟议的研究利用乳液模板来生成可注射的、可生物降解的支架，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.