CHEMICAL, STRUCTURAL, AND MORPHOLOGICAL STUDIES ON CALCIUM PHOSPHATES

磷酸钙的化学、结构和形态研究

• 批准号: 4692600
• 负责人: E D EANES
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF DENTAL & CRANIOFACIAL RESEARCH
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/4692600
• 关键词: X ray crystallography; analytical chemistry; apatites; calcification; calcium phosphate; carbonates; chemical reaction; chemical structure; chromatography; crystallization; cytoplasm; dental research; electron microscopy; extracellular matrix; ionophores; liposomes; physical chemical interaction; salts; tooth enamel; water solution

Calcium phosphate salts provide the hardness and rigidity which uniquely characterize normal, healthy bones and teeth. Developmental defects in the deposition of these salts or their destruction and loss by disease can severely impair the function of these skeletal tissues. The purpose of this project is to study the physical, chemical, and ultrastructual properties of these salts, and to clarify the kinetic and thermodynamic processes and the interactions with substances of biological interest that uniquely enable these salts to carry out their specialized role in vivo. The properties of calcium phosphate salts are being studied with a variety of ultrastructural and physical-chemical techniques such as electron microscopy, x-ray diffraction, surface area analyses, chromtographic and standard analytical chemistry procedures. Topics under current investigation include (1) the formation and properties of precipitates induced in microencapsulated posphate solutions by the ionophoric translocation of calcium ions across lipophilic solvent barriers, and (2) the growth dynamics of apatite crystals prepared under physiological-like aqueous solution conditions. The ionophore experiments are being conducted with liposomes with the goal of better understanding how matrix vesicles, the loci for initial mineralization in many vertebrate hard tissues, can concentrate to precipitable levels calcium and phosphate in their membrane and interior spaces. The purpose of the crystal growth experiments is to better elucidate the physicochemical and physiological factors delimiting the size and shape apatite crystals can attain various hard tissues.

磷酸钙盐提供了独特的硬度和刚性 表征正常，健康的骨骼和牙齿。 发育缺陷 这些盐的沉积或疾病的破坏和损失可以 严重损害了这些骨骼组织的功能。 目的 该项目是研究物理，化学和超微结构 这些盐的特性，并阐明动力学和热力学 过程以及与生物学兴趣物质的相互作用 独特的使这些盐在体内扮演专业角色。 正在研究磷酸钙盐的特性 超微结构和物理化学技术（例如电子） 显微镜，X射线衍射，表面积分析，染色体和 标准分析化学程序。 目前的主题 研究包括（1）沉淀物的形成和特性 通过离子摄取在微囊的phopphate溶液中诱导 钙离子跨亲脂溶剂屏障的易位，（2） 在生理样制备的磷灰石晶体的生长动力学 水溶液条件。 离子实验正在进行 脂质体的目的是更好地了解基质囊泡的方式 在许多脊椎动物硬组织中进行初始矿化的基因座，可以 将其浓缩到膜中的钙和磷酸盐水平 和内部空间。 晶体生长实验的目的是 更好地阐明了分解的物理化学和生理因素 大小和形状的磷灰石晶体可以达到各种硬组织。