Publication Type:
Journal ArticleSource:
Proc Natl Acad Sci U S A, Volume 102, Issue 46, p.16807-12 (2005)Keywords:
Animals, Diffusion, Female, Mice, Mice, Hairless, Mice, Inbred BALB C, Microscopy, Mineral Oil, Scattering, Radiation, Skin, Spectrum Analysis, RamanAbstract:
<p>Imaging living organisms with molecular selectivity typically requires the introduction of specific labels. Many applications in biology and medicine, however, would significantly benefit from a noninvasive imaging technique that circumvents such exogenous probes. In vivo microscopy based on vibrational spectroscopic contrast offers a unique approach for visualizing tissue architecture with molecular specificity. We have developed a sensitive technique for vibrational imaging of tissues by combining coherent anti-Stokes Raman scattering (CARS) with video-rate microscopy. Backscattering of the intense forward-propagating CARS radiation in tissue gives rise to a strong epi-CARS signal that makes in vivo imaging possible. This substantially large signal allows for real-time monitoring of dynamic processes, such as the diffusion of chemical compounds, in tissues. By tuning into the CH(2) stretching vibrational band, we demonstrate CARS imaging and spectroscopy of lipid-rich tissue structures in the skin of a live mouse, including sebaceous glands, corneocytes, and adipocytes, with unprecedented contrast at subcellular resolution.</p>