High aspect ratio, densely populated, pillar arrays for separations

在化学系化学测量和成像计划的支持下，诺克斯维尔田纳西大学的Michael Sepaniak教授和他的团队将解决创建用作微型液体相分离系统的化学分离柱阵列(PAC)的挑战。用于制造高纵横比支柱的原始工艺序列可产生机械坚固的系统。重要的是，所实现的高度有序的柱状阵列中的特征形貌可以扩展到纳米尺度。因此，与传统的填充柱和整体色谱柱以及传统的薄层色谱板相比，在封闭的压力驱动或开放的毛细管作用驱动模式下操作的流体结构提供了大幅提高分离效率和渗透率的潜力。在传统的分离系统中，孔隙率和纳米级的形态通常是随机的，因此，形态的异质性和相关的传质问题在带状展宽中起着重要的作用。相反，PACS提供了一种具有精确控制的纳米和微米结构的分离介质的替代方法。人们期待着对纳米级流体系统中的保留机制有新的见解。此外，先进的光刻技术将首次用于创建适用于高性能开放格式、二维空间分离的统一柱子结构。除了这项提议的科学目标之外，一个重要的目标是向年轻的研究人员介绍跨学科的科学和技术，包括微制造和纳米技术、表面性质的研究，以及开发新的分离、流体和超低容量检测/成像的仪器方法。招募少数族裔和传播研究成果的努力将利用我们以前的NSF项目和Sepaniak与波多黎各大学的合作等项目的先前经验。最后，还包括一个外展教育部分，包括为游客提供暑期研究体验，强调将地区高中师生组合带到德克萨斯大学校园。

With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, Professor Michael Sepaniak at University of Tennessee, Knoxville and his group will tackle the challenges of creating pillar arrays for chemical separations (PACS) that function as miniaturized liquid phase separation systems. An original processing sequence for the fabrication of high aspect ratio pillars yields mechanically robust systems. Importantly, the characteristic morphologies in the implemented highly ordered pillar arrays are scalable to nanometer dimensions. Thus the fluidic structures, operated in enclosed pressure-driven or open capillary action-driven modes, offer the potential for substantial improvements in separation efficiency and permeability over traditional packed and monolithic columns, as well as traditional thin layer chromatography plates. Porosity and nanoscale morphology in conventional separation systems is generally random and, therefore, morphological heterogeneity and related mass transfer issues play a significant role in band broadening. Conversely, PACS provides an alternative approach to separation media with precisely controlled nano- and micro-scale architectures. New insights into the retention mechanisms in nanoscale fluidic systems are expected. Moreover, advanced lithographic techniques will be used to create for the first time uniform pillar structures suitable for high performance open format, 2-D spatial separations. In addition to the scientific objectives of this proposal, an underpinning goal is to introduce young researchers to cross-disciplinary science and technology ranging from microfabrication and nanotechnology, studies of surface properties, and the development of new instrumental approaches to separations, fluidics, and ultra low volume detection/imaging. Efforts to recruit minorities and disseminate research results will be leveraged by prior experience with programs such as our prior NSF programs and Sepaniak's collaboration with the University of Puerto Rico. Finally, an outreach educational component is included that involves summer research experiences for visitors which emphasizes bringing area high school teacher-student combinations to the UT campus.