While analyzing the Raman peaks from the biological samples, I found a peak at 1890+/- cm-1 (which is a cumulative effect of the two peaks at 1870+/- and 1904+/- as found by Lorentz fit) which I am not able to assign to any biological molecules. I also have sifted through the literature and there, none of the authors see these peaks at all. Most of the biological samples show signature peaks from 100 cm-1 to 1700 or 1800 cm-1 and then the curve is flat till 2300+/- cm-1 after which peaks due to OH or CH vibrations are observed. Does anyone has any experience of observing these peaks at this value of the Raman shift? Or is it an experimental artifact, an affect of flourescence, background radiation or may instrumental (detector effect) ? Below is the screen shot of the spectra. Your guidance will be greatly appreciated.