Patent ID: 7558619

Claim:
A method of measuring the level of a selected molecule in a target sample, comprising: illuminating the target with light of a first wavelength F 1 ; illuminating the target with light of a second wavelength F 2 adjacent to the first wavelength F 1 ; receiving from the target emitted light resulting from each of the illuminations at wavelengths F 1 and F 2 and sampling the intensity of the emitted light at a range of wavelengths including a characteristic Raman emission wavelength Fc associated with the selected molecule and each of the illumination wavelengths; developing a first set of sampled intensity values for emitted light resulting from the illumination for wavelength F 1 , said sample including a value at or near the characteristic emission wavelength Fc associated with the selected molecule and wavelength F 1 , at least one sample adjacent the characteristic wavelength Fc but sufficiently displaced below that wavelength to exclude Raman emissions resulting from the illumination for wavelength F 1 and at least one sample adjacent the characteristic wavelength Fc but sufficiently displaced above that wavelength to exclude Raman emissions resulting from the illumination for wavelength F 1 ; developing a second set of sampled intensity values for emitted light resulting from the illumination for wavelength F 2 , said sample including a value at or near the characteristic emission wavelength Fc associated with the selected molecule and wavelength F 2 , at least one sample adjacent the characteristic wavelength Fc but sufficiently displaced below that wavelength to exclude Raman emissions resulting from the illumination for wavelength F 2 and at least one sample adjacent the characteristic wavelength Fc but sufficiently displaced above that wavelength to exclude Raman emissions resulting from the illumination for wavelength F 2 ; and deriving from ratios of corresponding values in the first and second sets of sampled intensity values an interpolated intensity value for emitted light between the characteristic wavelength Fc associated with each of F 1 and F 2 that removes the intensity value component due to non-Raman emissions, said interpolated intensity value derived from ratios of corresponding values in the first and second sets representing a measurement of the level of the selected molecule in the target sample.