Light sheet Raman micro-spectroscopy

Raman spectroscopy is a laser spectroscopic method which reveals detailed chemical information about a sample. Pointwise scanning produces chemical maps of heterogeneous samples such as biological tissue without prior staining. However the intrinsically low Raman scattering cross-sections result in long acquisition times, despite high excitation intensity in the focus that can damage the samples. Here, we present a novel technique termed Light Sheet Raman Micro-spectroscopy - an imaging spectrometer attached to a light sheet illumination microscope - to quickly acquire large hyperspectral Raman images. This method is more than 5 times faster than conventional approaches, while reducing the local excitation intensity over 300 fold. We show a stack of hyperspectral Raman images of a zebra fish eye with 1,024 × 1,024 × 50 spectra (17 min/slice) to demonstrate how the application of spontaneous Raman micro-spectroscopy can be extended to biomedical research and diagnosis based on directly utilising the molecular information present in the sample.