Developing Novel Biointerfaces and Biomaterials with Surface Plasmon Resonance and SPR Imaging

Much research has focused on the development of analytical methods to monitor a multitude of biological interactions including protein-carbohydrate, protein-lipid, and protein-DNA among others. Surface plasmon resonance (SPR) remains one of the most exciting techniques that allows for real-time data collection and label free detection amenable to many biological systems. This thesis focuses on the development of novel sensing interfaces/materials for biomolecular interaction analysis (BIA) with SPR and SPR imaging (SPRi).;The first half of this work focuses on the development of unique surface chemistry designs to examine biological interactions. Firstly, in an effort to augment understanding of lectin (protein)-carbohydrate interactions, SPR spectroscopy is used to display differential binding of lectins to various synthetic carbohydrates. This biointerface was later adapted to a high-density array format for SPR imaging detection. Secondly, to expand the use of SPR to large bioparticle detection another interface based on the generation of a mass-enhancing product at the sensing interface for highly sensitive and fast detection of E. coli is presented. Results indicate a multi-fold signal enhancement of E. coli cells in buffer and on spinach leaves.;The second part of this thesis focuses on the development of new substrates for both SPR and SPR imaging experiments. Firstly, the fabrication of ultra-thin (ca. 5--8 nm) glass layers on top of a gold surface for SPR biosensing applications is demonstrated. This nanoglassy layer is created by employing a high-pressure, low-volume paint gun technique, resulting in ultra-thin and fracture-free substrates for biosensing applications including monitoring membrane protein interactions in real-time. Finally, the facile fabrication of gold-coated etched glass substrates for SPR imaging that reduces background resonance 5-fold in situ compared to the standard gold island array platform is presented. The etching of the glass substrate induces a variation in the resonance condition and thus in the resonance angle between the etched wells and the surrounding area, leading to the isolation of the array spot resonance with a significant reduction of the background resonance. Additionally, these chips enhance the SPR evanescent field intensity 3-fold compared to standard planar gold chips and significantly enhance SPR imaging surface sensitivity.