We have previously demonstrated a total internal reflection, wide-field CARS microscope, where the signal is enhanced with the aid of a thin gold layer that supports surface plasmon polariton resonances. This surface-enhanced CARS microscope is capable of generating images of lipid structures in close proximity (<100 nm) to the glass substrate at excitation densities that are 4 orders of magnitude lower than in point-scanning CARS microscopy. In this contribution, we demonstrate its application to visualizing lipids in aqueous media, including imaging of cells, with a unique surface-sensitive contrast that cannot be obtained with conventional CARS microscopy.
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