MRI: Acquisition of Light Scattering Instruments for Nanoparticle Characterization

0923316 Van KeurenGeorgetown U“该奖项是根据2009年美国复苏和再投资法案(公法111-5)资助的。”技术摘要：静态和动态光散射提供分子质量和/或颗粒大小的实时、非侵入性表征。它们是表征聚合物分散体、颜料、胶体等材料的强大技术。这项提议是为了购买一套光散射仪器，供乔治敦大学化学和物理系的研究人员使用。这两个部门的大量研究活动涉及大分子和纳米粒子系统，包括大分子凝胶、聚合物胶体和分子聚集和自组装的研究。这套仪器的主要组件将是一个多角度静态光散射仪、一个动态光散射仪和一个差动折射仪，所有这些都来自怀亚特科技公司(加利福尼亚州圣巴巴拉)。有了这些，我们将能够测量几纳米到几微米范围内的颗粒尺寸，更重要的是，观察分子组装形成凝胶、晶体或纳米颗粒的时间依赖性。这些仪器将主要由物理系和化学系的五名教员以及他们的学生和其他合作者使用，项目范围从疟疾色素的结晶到凝胶的形成，再到与肾脏和胆结石形成有关的结晶。这些仪器的获得也将对乔治敦大学科学系之间已经相当多的跨学科活动产生重大影响，并为本科生和研究生提供机会发展这一重要分析方法的专业知识。莱曼摘要：当光线照射到小颗粒时，其中一部分会分散到其他方向；这对日常生活中经历的许多影响都有影响，从看到太阳光中的尘埃颗粒到天空的颜色。光是如何散射的，可以作为一种强大的测量技术来了解它散射的对象。特别是，光散射方法对于测量太小而无法用光学显微镜观察的物体的大小和形状很有用，比如纳米颗粒。乔治城大学的一些科学家参与了纳米颗粒如何形成的研究，并正在开发新型纳米材料。这项提议是为了获得一套最先进的光散射仪器，使这些材料能够被实时测量，而不会干扰它们的合成。其中一种仪器将用于静态光散射：测量光通过颗粒悬浮液时的角扩散。另一种是动态光散射，它使用散射光强度的快速波动来确定颗粒大小。这些仪器将主要由物理系和化学系的五名教员以及他们的学生和其他合作者使用，项目范围从疟疾色素的结晶到凝胶的形成，再到与肾脏和胆结石形成有关的结晶。这些仪器的获得也将对乔治敦大学科学系之间已经相当多的跨学科活动产生重大影响，并为本科生和研究生提供机会，发展这一重要分析方法的专业知识。

0923316Van KeurenGeorgetown U."This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)."Technical Summary: Static and dynamic light scattering provide real-time, noninvasive characterization of molecular masses and/or particle sizes. They are powerful techniques for characterizing materials such as polymer dispersion, pigments, colloids, etc. This proposal is for the acquisition of a suite of light scattering instruments to be used by researchers in the departments of Chemistry and Physics at Georgetown University. A large amount of the research activities in these two departments involves macromolecular and nanoparticles systems, including studies of macromolecular gels, polymer colloids and molecular aggregation and self-assembly. The main components of this instrument suite will be a multi-angle static light scattering apparatus, a dynamic light scattering attachment, and a differential refractometer, all from Wyatt Technology Corporation (Santa Barbara, CA). With these, we will be able to measure particle sizes in the range of several nanometers to several microns and more importantly, look at the time dependence of the assembly of molecules to form gels, crystals or nanoparticles. The instruments will be used primarily by five faculty members in the Physics and Chemistry departments, as well as their students and other collaborators, on projects ranging from studies of the crystallization of malaria pigment to the formation of gels to crystallization related to kidney and bile stone formation. The acquisition of these instruments will also have a significant effect on the already considerable amount of interdisciplinary activities among the science departments at Georgetown and provide an opportunity for undergraduate and graduate students to develop expertise in this important analytical method.Layman Summary: When light strikes small particles, part of it is scattered in other directions; this has many effects experienced in daily life, from the ability to see dust particles in a beam of sunlight to the color of the sky. How light is scattered can be used as a powerful measurement technique for learning about the objects from which it scatters. In particular, light scattering methods are useful for measuring sizes and shapes of objects too small to observe with optical microscopes, such as nanoparticles. A number of scientists at Georgetown University are involved in studying how nanoparticles form and are developing new types of nanomaterials. This proposal is for acquiring a set of state of the art light scattering instruments that will enable these materials to be measured in real time and without disturbing their syntheses. One instrument will be for static light scattering: measuring the angular spread of light as it passes through a suspension of particles. The other will be for dynamic light scattering, which uses the rapid fluctuations in the intensity of the scattered light to determine particle sizes. The instruments will be used primarily by five faculty members in the Physics and Chemistry departments, as well as their students and other collaborators, on projects ranging from studies of the crystallization of malaria pigment to the formation of gels to crystallization related to kidney and bile stone formation. The acquisition of these instruments will also have a significant effect on the already considerable amount of interdisciplinary activities among the science departments at Georgetown and provide an opportunity for undergraduate and graduate students to develop expertise in this important analytical method.