3D Nanoprinting via Controlled Assembly of Molecules

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.