Resonance Raman detection of carotenoid antioxidants in living human tissues

We have used resonance Raman scattering as a novel noninvasive optical tech nology to measure carotenoid antioxidants in living human tissues of health y volunteers. By use of blue-green laser excitation, clearly distinguishabl e carotenoid Raman spectra superimposed on a fluorescence background are ob tained. The Raman spectra are obtained within less than a minute, and the r equired laser light exposure levels are well within safety standards. Our t echnique can be used for rapid screening of carotenoid levels in large popu lations and may have applications for assessing antioxidant status and the risk for diseases related to oxidative stress. (C) 2001 Optical Society of America.