The plasmonic enhancement of Raman signals provides a sensitive label-free method of chemical analysis, which we use for nanoscale chemical imaging and nanomolar analyte detection. Raman spectroscopy has long provided chemical specific detection; however, the low intrinsic signal requires additional enhancement for trace analyte characterization. The first part of this talk will present results using plasmon coupling between a functionalized nanoparticle and a gold nanoparticle atomic force microscope tip to investigate protein receptors in cellular membranes.  This tip enhanced Raman (TERS) experiment obtains chemical, structural, and spatial information simultaneously. In protein-ligand binding experments, our results show signal characteristic of both the ligand, bound to a nanoparticle probe, and also the target protein.  The second part of this presentation will demonstrate our approach to high sensitivity Raman detection in flow.  The Raman enhancements from a planar nanostructure array we developed enable surface enhanced Raman scattering (SERS) measurements on millisecond time scales. The combination of these nanostructured surfaces with fluid dynamics enables ultrasensitive, high-throughput Raman characterization. Detection of diverse analytes incorporating flow injection analysis and capillary electrophoresis separations demonstrate the utility of our approach.  Our results provide insight into the origins and utility of plasmon enhanced Raman signals for ultrasensitive detection and imaging.