Novel Nanorods for High Efficiency Medical Imaging Applications

描述（由申请人提供）：一种新型高性能x射线荧光粉屏幕将基于嵌入透明聚合物基质中的点状棒核/壳纳米棒（NR）结构开发，应用于蛋白质晶体学，数字放射学和乳房x光摄影，以及许多其他重要的成像和照明应用。目标是实现高空间分辨率，非常快的时间响应，最小的余辉，最小的自吸收和优异的x射线转换效率。我们的纳米复合荧光粉屏幕将通过辐射监测设备（RMD）进行x射线测试，并与等效球形量子点（QD）屏幕和“传统”微晶ZnSe:Cu，Cl和Gd2O2S:Tb荧光粉屏幕进行比较。虽然由微米大小的荧光粉制成的荧光粉屏幕是高效、明亮的x射线转换器，但它们的大颗粒尺寸会产生大量的散射，这限制了它们的空间分辨率。初步的理论和实验研究表明，透明聚合物基质屏幕中的纳米荧光粉比微米级荧光粉具有更高的空间分辨率。与球形量子点相比，NR表现出更大的Stokes位移，以最小化自吸收。此外，它们的快速衰减时间和低余辉特性将确保响应时间比现有荧光粉快几个数量级。此外，为了增加x射线吸收，可以使用高z材料制作NR结构来增加x射线吸收，并调整其光谱发射以匹配CCD传感器的光谱灵敏度。具体而言，在第一阶段，我们将制备NR结构和相关筛选技术，并量化其x射线光致发光性能。如果我们能够证明这些NR结构在空间分辨率、时间分辨率和自吸收方面明显优于现有的微米级晶体荧光粉和传统的球形量子点，那么第一阶段的成功将得到证明。在第二阶段，我们将开发合成大量高质量纳米晶体的技术，并优化蛋白质晶体学和医学成像CCD探测器的大屏幕特性。基于核磁共振的x射线转换胶片将在数字放射照相、晶体照相、乳房x线照相术和各种其他生物医学成像应用中有重要的应用，提高它们对美国国立卫生研究院、分子生物学和整个医学界的价值。

DESCRIPTION (provided by applicant): A new class of high-performance X-ray phosphor screens will be developed based on dot-in-a-rod core/shell nanorod (NR) structures embedded in transparent polymer matrices, with applications to protein crystallography, digital radiography and mammography, as well as a host of other important imaging and lighting applications. The goal is to achieve high spatial resolution, very fast time response, minimum afterglow, minimum self-absorption and excellent X-ray conversion efficiency. Our nano- composite phosphor screens will be X-ray tested by Radiation Monitoring Devices (RMD) and compared with equivalent spherical quantum dot (QD) screens and "conventional" micro-crystalline ZnSe:Cu,Cl and Gd2O2S:Tb phosphor screens. Although phosphor screens made from micron-sized phosphors are efficient, bright X-ray converters, their large particle size produces a great deal of scatter, which limits their spatial resolution. Preliminary theoretical and experimental studies show that nanophosphors in a transparent polymer-matrix screen exhibit significantly higher spatial resolution than micron-sized phosphor particles. Compared with spherical QDs, NR exhibits much larger Stokes shift to minimize self-absorption. In addition, their fast decay times and low afterglow characteristics will ensure response times orders of magnitude faster than existing phosphors. Moreover, to increase X-ray absorption, NR structures can be made from high-Z materials to increase X-ray absorption and their spectral emission tuned to match the spectral sensitivity of CCD sensors. Specifically in Phase I, we will prepare NR structures and related screening techniques, and quantify their X-ray photoluminescence performance. Success in Phase I will be proven if we can show that these NR structures are significantly better than existing micron-sized crystalline phosphors and conventional spherical quantum dots, in terms of spatial resolution, time resolution, and self-absorption. In Phase II, we will develop the techniques to synthesize large quantities of high quality nanocrystals, and optimize large screen characteristics for protein crystallography and medical imaging CCD detectors. NR-based X-ray converting films will have significant applications in digital radiography, crystallography, mammography, and various other biomedical imaging applications, enhancing their value to the NIH and to the molecular biology and medical communities as a whole. PUBLIC HEALTH RELEVANCE: The proposed nanorod luminescent structures will significantly enhance the performance of X-ray imaging compared to current state-of-the art. They will have applications in digital radiography, crystallography, and various medical imaging applications, enhancing their value to the NIH and to the molecular biology and medical communities as a whole.