Divided shifted Raman spectroscopy for carotenoid detection

Abstract

We have developed a compact portable instrument for resonance Raman spectroscopy of carotenoid molecules in skin tissue. Our application focuses on the 1525 cm −1 Raman line common to all carotenoids. We use a divided shifted Raman spectroscopy (DSRS) technique that reduces sensitivity to detector drift and error. Two wavelength-narrowed LEDs illuminate the sample, and scattered light in four different wavelength channels is measured. This multi-spectral approach has single-photon sensitivity and compares favorably with laser-based Raman measurements in terms of accuracy, repeatability, and measurement time.