Nonlinear interferometric vibrational imaging for fast label-free visualization of molecular domains in skin.

The most prevalent molecular constituents of skin are spatially mapped by the use of nonlinear interferometric vibrational imaging, a coherent anti-Stokes Raman scattering (CARS)-based technique. Raman-like profiles over the range from 2,800 to 3,000 cm(-1) are acquired by means of completely suppressing the non-resonant background, allowing the generation of images based on the molecule-specific spectral profiles over the probed region with high spatial resolution. A simple algorithm that maps spectral content to color allows the visualization of histology in a manner analogous to that obtained with more conventional staining procedures (e.g., hematoxylin-eosin), but faster and with the benefit of having access to localized spectra, which could further enhance the potential for diagnosis of diseases, especially during the early stages of development.