3D Nanoprinting via Controlled Assembly of Molecules

在化学系大分子、超分子和纳米化学(MSN)计划的支持下，加州大学戴维斯分校的刘钢宇教授计划以纳米级的精度控制脂质等分子在太空中的排列方式。控制分子的组装方式是化学研究的前沿领域，需要对分子在组装过程中如何相互作用有深入的理解。这项工作设想通过以下方式实现这些目标：(1)能够输送含有具有吸引力的分子的超小液滴；(2)在液滴干燥过程中控制空间限制的几何形状；以及(3)控制每个结构中的分子堆积。对这些基本化学属性的更好理解有可能将添加剂制造的能力扩展到纳米级，即3D纳米打印，这可用于生产纳米传感器、量子电子器件、工程细胞和新材料。与当地一所社区大学合作，培训和研究将把来自代表性不足群体的研究生和本科生带到纳米技术的前沿，并帮助他们成为3D纳米打印等领域未来化学领域的领导者。使用最先进的纳米流体传输与原子力显微镜的集成，超小液滴、亚飞升解决方案将被交付到衬底上的指定位置。将系统地研究实验参数(例如，孔径大小、输送压力、接触时间、局部表面张力)对纳米流体装置中单个液滴体积的影响，以实现亚临界输送。在溶剂蒸发过程中，分子将在缩小的液滴边界的引导(或控制)下组装，从而控制每个结构中的分子堆积。这项拟议的工作旨在通过克服具有吸引力的分子间相互作用(例如，与碳水化合物)和集体分子相互作用(例如，与脂质)来展示受控沉积的概念。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Macromolecular, Supramolecular and Nanochemistry (MSN) Program in the Division of Chemistry, Professor Gang-yu Liu of University of California, Davis, plans to control how molecules, such as lipid, arrange in space, with nanometer precision. Controlling how molecules assemble represents a frontier area of research in chemistry, requires the proposed deep understanding of how molecules interact during the assembly processes. The work envisions achieving these goals by, (1) enabling the delivery of ultrasmall droplet (sub-aL) of solutions containing molecules with attractive interactions; (2) controlling the geometry of spatial confinement during drying of droplet, and (3) controlling the molecular packing within each structure. Better understanding of these fundamental chemical attributes has the potential to extend the capability of additive manufacturing to the nanometer scale, i.e., 3D nanoprinting, which could be used for production of nanosensors, quantum electronic devices and engineered cells and new materials. In conjunction with a local community college, the training and research will bring graduate and undergraduate students from under-represented groups to the forefront of nanotechnology and help position them to be future leaders in chemistry in areas such as 3D-nanoprinting.Using a state-of-the-art integration of nanofluidic delivery with an atomic force microscope, ultrasmall droplets, sub-femtoliter solutions will be delivered to designated locations on substrates. The impact of experimental parameters (e.g., aperture size, delivery pressure, contact time, local surface tensions) on the individual droplet volume in the nanofluidic setup will be systematically investigated to achieve sub-aL delivery. During solvent evaporation, molecules will assemble as guided (or controlled) by the shrinking droplet boundaries thereby controlling the molecular packing within each structure. The proposed work aims to demonstrate the concept of controlled deposition by overcoming attractive intermolecular interactions (e.g., with carbohydrates) and collective molecular interactions (e.g., with lipids).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.