Modifications of Planar and Nanostructured Surfaces for the Interrogation of New Sensor Designs

130 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2009.Surfaces and the chemistry that defines them are critical parameters in the application of functional devices to the extended field of sensing in biotechnology. From microfluidic devices to immunoassay platforms the modification of surfaces play an important role in dictating how interactions with biomoleulces will proceed. Simple surfaces such as self-assembled monolayers provide an ample starting point for the investigation of these interactions and have been used in a manner that provides a capture strategy for analyzing cellular release. As an alternative to using self-assembled monolayers as the basis for surface modifications, we have designed a class of polymers that are both easily synthesized and inherently resistant to nonspecific adsorption of proteins when attached to a surface. Polymeric materials offer a wide range of possible functionality and the ability to impart these functionalities onto both planar and nanostructured surfaces. Advances in lithographic techniques coupled with a better understanding of how surface plasmons respond to changes in the dielectric at the interface has culminated in the development of plasmonic crystals sensors. As a model system, a responsive hydrogel infused with gold nanoparticles coupled to the surface of a plasmonic crystal was able to optically detect small changes in the pH of a buffered solution even in the absence of bulk refractive index changes. To further extend the utility of these nanostructured surfaces optical imaging of patterned thin films of small molecules and proteins was studied to gain insight into the utility of the plasmonic crystals as a platform for monitoring changes in cellular morphology in a label free format.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD