Label-free imaging of lipid droplets in cells by stimulated Raman microscopy

Recent technological developments in ultrafast laser physics have permitted to make new kind of nonlinear microscopies, as microscopy based on Stimulated Raman scattering. These techniques are based on vibrational contrast mechanism for imaging with high sensitivity, high spatial and spectral resolution and 3D sectioning capability. The interest in the study of lipids and the possibility to image lipid droplets, thanks to their isolated Raman peaks associated with vibrational C-H bond, have encouraged investigation and identification of lipid structures inside cells, taking advantage of Stimulated Raman Scattering (SRS) imaging. In this work, we report and discuss label free images on biological environmental and structural analysis, to detect lipid microstructures inside adipocyte cells.