NANOMATERIALS TO BIOSENSORS: A BENCH-TOP RAPID PROTOTYPING APPROACH

Nanofabrication has received substantial interest from scientists and engineers because of its potential applications in many fields. This was because nanoscale structures have unique properties that cannot be observed or utilized at other size scales. Our living environment and many of our daily necessities had been strongly influenced by these techniques. Computers, electronics, housewares, vehicles, and medical care are now all affected by this explosive nanotechnology. However, traditional methods in controlling nanoscale features and their properties were often time-consuming and expensive. The objective of my research was to design, fabricate, and test nanostructure platforms using a unique toolbox of bottom-up lithographic techniques recently developed in our laboratory. These novel methods can be utilized for the rapid prototyping of nanoscale patterns in a much easier and more economical way. Specifically, we also focused on applying these nanoscale patterns as sensor platforms. These platforms were easily produced with our unique methods, and provide ultra sensitive capability to detect diverse chemical or biological species. The demonstration of capabilities and applications of our unique technologies includes the following projects. Chapters II and III describe a simple, inexpensive, and rapid method for making metal nanoparticles ranging between 10 nm and 100 nm in size through metal photoreduction with templates. The process can be completed in approximately 11 minutes without the use of a clean room environment or vacuum techniques. A simple label-free biosensor fabrication method based on transmission localized surface plasmon resonance (T-LSPR) of this platform is also demonstrated. Chapters IV and V present a nanoscale patterning technique for creating diverse features in polymers and metals. The process works by combining evaporative ring staining with a colloidal templating process. Well-ordered hexagonally arrayed nanorings, double rings, triple rings, targets, and holes were all easily prepared. A line width as thin as ~15 nm can repeatably be performed with this technology. Finally, Chapter VI demonstrates an ultra-sensitive plasmonic optical device based on hexagonal periodic nanohole metal films produced through our evaporative templating technique. The optical properties of these sub-wavelength periodic hole array metal films are discussed.