Development of Advanced Methodologies for Three-dimensional Nanoprinting

Download or read book Development of Advanced Methodologies for Three-dimensional Nanoprinting written by Joao Francisco Ventrici de Souza and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Three-dimension (3D) printers are commercially available with resolution as high as micrometers. Further miniaturization would require development of both materials, instruments, as well as methodology in order to attain required spatial precision to reach nanometer scale. This dissertation reports our recent progress in producing 3D nanostructures using an atomic force microscopy (AFM) based methods. First, we use AFM to investigate and to better understanding the tip-molecular and molecule-molecules interactions using bilayer systems to begin the studies. The structure, phase behavior and properties of cellular membranes are determined by their composition which includes phospholipids, sphingolipids, sterols, and proteins with various level of glycosylation. Due to the intricate nature of cellular membranes, a plethora of in vitro studies have been carried out with model membrane platforms that capture specific properties such as fluidity and permeability, but vastly simplify the membrane composition in order to focus in detail on a single property or function. Supported lipid bilayer (SLB) systems are one such platform and this work focuses specifically on the characterization and engineering of SLB systems. A number of characterization methods which take advantage of the flat orientation of SLBs are described and references which go into more depth are included. This dissertation reports quantity and compares the quality of the resulting SLBs in correlation with a variety of gel and fluid compositions, preparation techniques and parameters, to generate general rules of thumb to guide preparation of designed SLB systems. Finally, our approaches to reduce morphologic defects are delineated. Secondly, we use modified AFM technology for both printing and characterization. By putting molecules to the AFM tips, then transfer them to surfaces via scanning, nanometer scale lines, cross-grids, and pyramids were constructed following designed geometry and size. The products were also characterized in situ using AFM to demonstrate the fidelity and spatial precision. Another approach taken in this dissertation towards the 3D nanoprinting goal is the direct delivery via combining AFM with microfluidic probes. Direct writing methods are a convenient way to produce 3D structures. The capability to extrude materials through a nozzle makes this method compatible with a wide range of inks. Although this method has been routinely used in the fabrication of structures on the microscale, the new challenge is to achieve 3D printing on the nanoscale. This dissertation reports the miniaturization of 3D structure production to line widths of 130 nm and heights of 3.1 nm. Three layered grids and custom designed objects were printed with the direct delivery of ultraviolet curable polymer. using a modified atomic force microscope (AFM). The enabling aspects of 3D nanoprinting should have significant impact on a broad range of applications including tissue engineering, biomaterials, biomimetics, nanophotonics materials, and nanodevices.