Benchtop ultra-small angle X-ray scattering system for nanoscale and nanoparticle characterization

我们建议购买NANOPIX迷你实验室规模的超小角度x射线散射（USAXS）系统来检测纳米颗粒的尺寸，孔隙率和聚集行为。Marangoni团队将USAXS技术用于研究可食用脂肪的纳米级晶体结构。对一种脂肪进行15分钟的分析，就能得到长度从4纳米到10微米的结构信息。技术和理论的发展都对这些材料的结构及其与功能的关系产生了有价值的见解。从这项研究中得出的最重要的参数之一是晶体纳米血小板（CNP）的大小。CNPs的长度在100纳米到400纳米之间，宽度在60纳米到100纳米之间，厚度在20纳米到40纳米之间。CNPs对组分、冷却速率和剪切的变化极为敏感。例如，我们报道了巧克力的回火过程导致CNP尺寸减少了10倍。因此，我们开发了一种用于这些食品材料的纳米级结构探针。这些实验必须在芝加哥阿贡国家实验室的同步加速器x射线设备上进行，因为圭尔夫大学没有所需的设备。使用设备的困难严重限制了可以进行的研究的类型和数量。NANOPIX机器将允许我们对脂肪和油的加工、成分和纳米级晶体结构之间的相关性进行更多的探索性研究。确定这种相关性对于用油凝胶和结构乳剂代替硬脂肪在不影响功能和质量的情况下改善营养特性至关重要。同样的方法将扩展到蛋白质凝胶。Pensini实验室感兴趣的是开发具有可调孔隙度的颗粒，用于靶向递送试剂以修复地下污染物。Pensini实验室还对使用由天然乳化剂（如大豆卵磷脂，一种表面活性剂样脂肪）稳定的乳液凝胶处理地表水上的化学泄漏感兴趣。在净化地表水所需的时间内，乳液凝胶必须是稳定的。凝胶稳定性与油水界面乳化剂膜的结构和稳定物质（如表面活性剂样脂肪（如卵磷脂））的聚集行为密切相关。Zhou的实验室对了解絮凝蛋白、细胞外物质和水中精细分散的有机物的大小和结构感兴趣，以优化水净化高级过滤膜的设计。根据污染物絮凝体的大小要求，设计出具有最佳膜孔径的膜。此外，污染物絮凝体的孔隙率与絮凝体的强度有关。周的实验室对使用添加剂来提高絮凝体强度很感兴趣，因为强絮凝体在水处理厂受到剪切时不太容易分解。＊＊＊＊＊

We propose to purchase a NANOPIX mini lab-scale Ultra-Small Angle X-ray Scattering (USAXS) system to examine the size, porosity and aggregation behavior of nano-particles. The USAXS technique was implemented for the study of the nanoscale crystalline structure of edible fats by the Marangoni group. A 15-minute analysis of a fat would yield structural information at length scales from 4 nm to 10 um. Both technique and theory developed yielded valuable insight into the structure of these materials and its relationship to functionality. One of the most important parameters derived from this study is the size of a crystalline nanoplatelet (CNP). CNPs can have lengths between 100 nm and 400nm, widths between 60 nm and 100nm and thicknesses between 20 nm and 40nm. CNPs are extremely sensitive to changes in composition, cooling rate and shear. For example, we reported that the tempering process in chocolate led to a 10-fold reduction in CNP size. We have thus developed a structural probe for the nanoscale in these food materials. These experiments had to be carried out at the synchrotron X-Ray facility at Argonne National Labs in Chicago because the required equipment is not available at the University of Guelph. The difficulty in accessing the equipment severely limits the types and number of studies that can be carried out. The NANOPIX machine will allow us to carry out more exploratory studies on the correlation between the processing of fats and oils, their composition and their nanoscale crystalline structure. Defining this correlation is crucial to replace hard fats with oleogels and structured emulsions to improve nutritional properties without affecting functionality and quality. The same approach will be extended to protein gels. The Pensini lab is interested in developing particles with tunable porosity for the targeted delivery of reagents to remediate subsurface contaminants. The Pensini lab is also interested in treating chemical spills on surface waters using emulsion gels stabilized by natural emulsifiers (e.g. soy lecithin, a surfactant-like fat). Emulsion gels must be stable during the time required to decontaminate surface waters. Gel stability is strongly correlated to the structure of the emulsifier films at the oil-water interface and to the aggregation behaviour of the stabilizing species such as surfactant-like fats (e.g. lecithin). The Zhou lab is interested in understanding the size and structure of flocculated proteins, extracellular material and finely dispersed organic matter in water, to optimize the design of advanced filtration membranes for water purification. The size of the contaminant flocs is required to design membranes with the optimal membrane pore size. Also, the porosity of contaminant flocs is correlated with the strength of the flocs. The Zhou lab is interested in using additives to improve floc strength, because strong flocs are less prone to disaggregating when subject to shear in water treatment plants. *****