Rapid Near-Infrared Raman Spectroscopy of Human Tissue with a Spectrograph and CCD Detector

Abstract

We demonstrate the use of a single-stage spectrograph and charge-coupled-device (CCD) detector to collect near-infrared (NIR) Raman spectra from intact human arterial tissue. With 810-nm excitation, the fluorescence emission from human artery is sufficiently weak to allow observation of Raman bands more rapidly with the spectrograph/CCD system than with 1064-nm excited FT-Raman systems. We also present a method for removing the broad-band emission from the spectra by computing the difference of two emission spectra collected at slightly different excitation frequencies. Our results indicate that NIR Raman spectra can be collected in under one second with the spectrograph/CCD system and an optical fiber probe, opening the possibility of in vivo clinical applications.