High-Speed Coherent Raman Fingerprint Imaging of Biological Tissues

Nat Photonics. 2014:8:627-634. doi: 10.1038/nphoton.2014.145.

Abstract

An imaging platform based on broadband coherent anti-Stokes Raman scattering (BCARS) has been developed which provides an advantageous combination of speed, sensitivity and spectral breadth. The system utilizes a configuration of laser sources that probes the entire biologically-relevant Raman window (500 cm-1 to 3500 cm-1) with high resolution (< 10 cm-1). It strongly and efficiently stimulates Raman transitions within the typically weak "fingerprint" region using intrapulse 3-colour excitation, and utilizes the nonresonant background (NRB) to heterodyne amplify weak Raman signals. We demonstrate high-speed chemical imaging in two- and three-dimensional views of healthy murine liver and pancreas tissues and interfaces between xenograft brain tumours and the surrounding healthy brain matter.