Novel near-infrared Raman spectroscopy of biological fluids

Raman spectroscopy sensitivity in medical applications, is limited by the fact that most biological samples. are strongly fluorescent in the visible, which makes the much weaker Raman signals at the same wavelengths nearly impossible to detect. Our group is working to combine rapid wavelength modulation, which is important for overcoming drift noise, with multichannel wavelength detection, which is essential for high-throughput Raman spectroscopy systems. One essential component of our system is a wavelength-tunable diode laser. Early applications of this work have focused upon the detection of hemoglobin, myoglobin, and creatinine in urine samples. Urine fluoresces enough at 830 nm excitation that the Raman peaks of these chemicals are nearly invisible in a conventionally-obtained Raman spectrum