Research Equipment: Pulsed Field Gradient NMR Diffusion Probe

该项目支持为科罗拉多矿业学院（CSM）核磁共振设施最先进的核磁共振（NMR）光谱仪获取脉冲场梯度（PFG）扩散探针。该探测器提供的实验能力将大大提高CSM教师和学生的研究和教育机会。位于四个不同部门的六个独立研究项目将首先使用PFG探针来产生重要的新科学和工程知识。此外，研究生和本科生将能够学习和使用这个现代工具，通过测量扩散和扩散边界来研究复合介质和复杂材料。该探针对首席研究员（PI）研究复合膜材料，特别是哺乳动物表皮（皮肤）特别有价值。复合材料中的化学渗透可以通过一种或多种途径进行。对于复合材料来说，传统的化学物质通过膜进行传输的定量方法——扩散池测量，提供了总体传输的信息，但无法了解实际的传输路径或这些路径中的局部扩散系数。使用PFG扩散探针，PI将测量从人类和动物受试者身上切除的角质层（SC）中选定的化学示踪剂（包括19F）的自扩散系数。SC是皮肤的最外层，也是大多数化学物质进出身体的主要屏障。这些扩散探针研究的目的是了解表皮屏障功能的机制。这种理解将用于开发预测、增强和控制皮肤渗透的方法，以及开发用于估计皮肤吸收的替代皮肤样品的材料。用于研究SC复合膜的研究策略也将用于研究其他复杂膜，无论是生物的还是非生物的。除了PI的项目外，来自化学工程和石油炼制、工程和地球物理三个系的其他五名CSM教员（辅助用户）也提出了利用PFG扩散探针进行研究的建议。核磁共振pfg方法已经在本提案中描述的所有研究项目中得到了证明，尽管测量的数量非常少，并且使用该设备产生新知识的机会很大。

9905569BungeThis project supports acquisition of a pulsed field gradient (PFG) diffusion probe for the state-of-the-art nuclear magnetic resonance (NMR) spectrometer at the Colorado School of Mines (CSM) NMR Facility. The experimental capabilities provided by this probe will greatly enhance research and educational opportunities to CSM's faculty and students. Six separate research programs housed in four different departments will initially use the PFG probe to produce significant new scientific and engineering knowledge. In addition, graduate and undergraduate students will be able to learn about and use this modern tool for investigating composite media and complex materials through measurements of diffusion and boundaries to diffusion. This probe will be particularly valuable to the principal investigator's (PI's) studies of composite membrane materials, specifically mammalian epidermis (skin). Chemical penetration in composite materials can proceed by one or more pathways. For composite materials, diffusion cell measurements, the traditional method of quantifying chemical transport through membranes, provide information on overall transport, but no insights into the actual pathways or the local diffusion coefficients in those paths. Using the PFG diffusion probe, the PI will measure self-diffusion coefficients of selected chemical tracers (those that include 19F) in stratum corneum (SC) excised from human and animal subjects. The SC is the outermost layer of skin and the main barrier to passage of most chemicals into and out of the body. The aim of these diffusion probe studies is to understand the mechanisms of epidermal barrier function. This understanding will then be used in developing methods to predict, enhance, and control dermal penetration and in developing materials to replace skin samples for estimating dermal absorption. The investigative strategies used to study the SC composite membrane will also be useful in the study of other complex membranes, either biological or non-biological. In addition to the PI's program, five other members of the CSM faculty (auxiliary users) from three departments (Chemical Engineering and Petroleum Refining, Engineering, and Geophysics) have proposed research investigations utilizing the PFG diffusion probe. The NMR-PFG method has been demonstrated for all of the research projects described in this proposal, although the number of measurements is extremely small and there is a great opportunity to produce new knowledge with this device.