The invention uses a resonance Raman spectrometer 1 for achieving the identification and quantitation of analytes including biomolecules, organic and inorganic molecules. According to the present invention, a) a sample 2 is deuterated 3 with D20 for facilitating identification and quantitation of analytes 4 of said sample, b) a monochromatic light 6 illuminates sample 2 of analytes 4 for producing Raman sample light 12 and rejecting Rayleigh light 14, c) the Raman sample light 12 is passed through a depolarizer 19 for producing randomized polarization components 20, d) a Raman sample spectrum 22 is generated, calibrated with respect to an absolute differential Raman cross-section standard in response to said randomized polarization components 22, e) the Raman sample spectrum 22 is provided to a spectral analyzer 24 for identification 26 and/or quantitation 28 of the analytes 4.