Figure 1
From: Chemically imaging bacteria with super-resolution SERS on ultra-thin silver substrates
Illustration of imaging process and interaction between the plasmonic surface and the cell wall. (a) Depiction showing the creation of enhanced electromagnetic field “hotspots” due to illumination of the silver plasmonic surface from below. (b) SEM image of the plasmonic surface created by depositing 10 nm silver and a 2 nm chromium adhesion layer upon a glass microscope coverslip. (c) Transmission spectrum of an ultrathin silver island film showing a clear plasmonic resonance dip. (d) Depiction of a cell adsorbed to the rough plasmonic surface. (e) Schematic depicting the interaction between the hotspots and the cell wall. SERS is emitted from the sample and collected by the same objective used to illuminate from below. (f) Schematic depicting the molecular structure of a cell wall on a gram negative and (g) a gram positive bacterial species.
