High-speed Raman imaging of cellular processes.

Raman scattering microscopy provides information about the distribution and chemical state of molecules in live cells without any labeling or modification. In recent years, the imaging speed of Raman microscopy has improved greatly owing to the development of instruments that can perform parallel acquisition of Raman spectra from multiple points. In this article, we review recent advances in high-speed hyperspectral Raman imaging and its application to observe various biological processes such as cell mitosis, apoptosis and cell differentiation. Furthermore, we discuss the recent progress in Raman tags for the specific observation of bioactive small molecules in complex biological systems, including the development of organelle-specific probes, imaging of lipid rafts in an artificial monolayer membrane and application as a structure-sensitive tag.