Comprehensive study of Inorganic Polyphosphates for Biomedical Engineering applications

需要新的和创新的材料和设备来对抗具有挑战性的临床应用，如慢性骨感染和难以根除的癌症肿瘤，许多现有的生物材料在可能的情况下被修改或应用到次优以满足这些需求。我们的研究计划调查一组被称为无机聚磷酸盐的材料是否可以用来填补这一关键角色。*无机聚磷酸盐是磷酸盐分子的长链，可以形成各种凝胶和玻璃。我们之前的研究表明，聚磷酸钙具有作为药物输送系统的潜力；药物可以在聚磷酸钙玻璃基质形成凝胶时被加载到基质中，然后随着基质的降解而释放。*计划有两个节目流。在第一个流程中，我们将研究不同链长的聚磷酸钠与不同带电金属离子(如钙、锶和铝)结合制成的聚磷酸盐凝胶和玻璃的结构、组成和流动性能。我们还将研究带正电荷的大分子(壳聚糖)与这些聚磷酸盐的相互作用，以确定凝胶所需的加工条件。*基于从这项研究和之前的观察中获得的理解，第二个项目流将侧重于将这些无机聚磷酸盐转化为各种形式，例如具有针对特定治疗需求量身定做的物理特性和药物输送能力的非常小的微珠和注射材料。这项研究的一个较长期的目标是研究如何使用新的和先进的制造工艺，如电纺和3D打印来制造由无机聚磷酸盐制成的支架。这样的支架将提供独特的三维结构来指导细胞附着和生长，以形成新的组织。*由于无机聚磷酸盐在许多生物功能中发挥作用，包括骨形成和血液凝固，还用于制造阻燃材料和许多工业应用，如环境净化，通过这项拟议的研究计划，增进我们对无机聚磷酸盐及其操作的基本理解，可能会对开发新的生物材料和生物医学设备产生更大的影响。

New and innovative materials and devices are needed to combat challenging clinical applications such as chronic bone infections and cancerous tumors that are difficult to eradicate, with many current biomaterials being adapted where possible or applied sub-optimally to meet these needs. Our research program investigates whether a group of materials known as inorganic polyphosphates can be used to fill this critical role. ***Inorganic polyphosphates are long chains of phosphate molecules that can be formed into a variety of gels and glasses. Our previous research has shown that calcium polyphosphates have the potential to be used as drug delivery systems; drugs can be loaded into the calcium polyphosphate glass matrix as it forms into a gel and are later released as the matrix degrades. ***Two program streams are planned. In the first stream we will investigate the structure, composition and flow properties of polyphosphate gels and glasses made with sodium polyphosphates of different chain lengths in combination with different charged metal ions (such as calcium, strontium, and aluminum). We will examine as well the interaction of large, positively charged molecules (chitosan) with these polyphosphates to determine the processing conditions required for gelling. ***Based on the understanding gained from this research and from earlier observations, a second program stream will focus on transforming these inorganic polyphosphates into various forms, such as very small micro-beads and injectable materials having physical properties and drug delivery capability tailored to the particular treatment needs. A longer-term goal of this research is to investigate how new and advanced manufacturing processes such as electrospinning and 3-D printing might be used to create scaffolds made of inorganic polyphosphates. Such scaffolds would provide unique three-dimensional structures to direct cell attachment and growth in order to form new tissues. ***As inorganic polyphosphates play a role in many biological functions, including bone formation and blood clotting, and are also used in the manufacture of fire retardant materials and in many industrial applications such as environmental decontamination, advancing our basic understanding of inorganic polyphosphates and their manipulation through this proposed program of research may have implications beyond the development of new biomaterials and biomedical devices.**