SBIR Phase I: Scalable Synthesis and Processing of Nanocrystalline Hydroxyapatite

这个小企业创新研究第一阶段项目将开发工艺和控制，以生产商业数量的纳米结构羟基磷灰石（HAP）生物材料，适用于承重骨科和牙科应用。尽管羟基磷灰石的骨导电性在许多临床应用中引起了人们的兴趣，但传统加工的羟基磷灰石材料由于相纯度和均匀性差，其烧结性能差，缺乏机械强度，因此受到限制。通过控制化学沉淀过程中反应物的混合方式、颗粒的回收和合成条件等物理过程，优化HAP的结晶度、化学计量学和颗粒形貌，从而优化HAP的机械强度。机械强度优化后的羟基磷灰石为纳米晶，具有更高的化学稳定性和热稳定性；这些特性将导致烧结性能的增强和最小的晶粒生长。因此，将获得具有优异化学均匀性、微观组织均匀性、超细晶粒尺寸和最小缺陷尺寸的全致密纳米晶HAP单体。最终，制备的纳米晶HAP整体材料具有优异的抗压强度（900 MPa）和弯曲强度（200 MPa）以及断裂韧性（1.3 mpam /2）。在商业上，这些纳米结构材料可以形成结构，并用于通常用于验证骨科植入物的实验模型。纳米结构的羟基磷灰石有助于更好的成骨细胞附着、增殖和矿化。

This Small Business Innovation Research Phase I project will develop processes and controls for producing commercial quantities of nanostructured hydroxyapatite (HAP) biomaterials suitable for load bearing orthopedic and dental applications. Though hydroxyapatite's osteoconductivity has generated interest in many clinical applications, conventionally processed hydroxyapatite materials have been limited by their poor sinterability and lack of mechanical strength attributed to poor phase purity and homogeneity. By controlling physical processes such as the method of mixing of reactants, particle recovery and synthesis conditions during the chemical precipitation of HAP, the crystallinity, stoichiometry and particle morphology of HAP will be optimized for mechanical strength. Hydroxyapatite optimized for mechanical strength will be nanocrystalline and possess increased chemical and thermal stability; these properties will lead to enhanced sinterability and minimal grain growth. As a result, fully dense, nanocrystalline HAP monoliths possessing superior chemical homogeneity, microstructural uniformity, ultrafine grain sizes and minimized flaw sizes will be achieved. In the final result, the nanocrystalline HAP monoliths produced will provide superior compressive (900 MPa) and bending (200 MPa) strengths as well as fracture toughness (1.3 MPam1/2).Commercially, these nanostructured materials can be formed into constructs and utilized in experimental models commonly employed to validate orthopedic implants.Nanostructured hydroxyapatites will contribute to better osteoblast attachment, proliferation and mineralization.