A novel evanescent field based fluorescence microscopy method named ‘waveguide evanescent field fluorescence (WEFF) microscopy’ was developed. WEFF microscopy, where fluorescence dyes are only excited within the evanescent field of a waveguide, can investigate surface and interface properties in biology and material sciences. We have utilized this microscope to image cell-substrate contact regions and solid thin films. WEFF microscopy can measure the separation distances between a cell and its substrate without complicated modeling and simulations compare to well-established methods such as total internal reflection fluorescence and surface plasmon resonance microscopes. In addition, the effect of lethal external agents on living cells was investigated in real time in vitro.
