Patent ID: 6996472

Claim:
A method for compensating for drift in fingerprint spectra due to differences in environmental factors that affect the metabolic state of microorganisms, wherein the fingerprint spectra are selected from the group consisting of mass spectra, infrared spectra, ion-mobility spectra, gas chromatograms, liquid chromatograms, and nuclear magnetic resonance spectra, and portions and combinations therefor—thereof, comprising: culturing under a first set of environmental factors a first microorganism and a second microorganism that is presumably metabolically similar to the first microorganism; wherein metabolically similar microorganisms are organisms that exhibit similar fingerprint spectra that change similarly in response to changes in the environment; measuring a fingerprint spectrum of the first microorganism cultured under the first set of environmental factors and a fingerprint spectrum of the second microorganism cultured under the first set of environmental factors; obtaining a fingerprint spectrum of the second microorganism cultured under a second set of environmental factors that differ from the first set of environmental factors and affect the metabolic state of the first and second microorganisms; deriving a relationship between the fingerprint spectrum of the second microorganism cultured under the first set of environmental factors and the fingerprint spectrum of the second microorganism cultured under the second set of environmental factors; and, applying the relationship derived for the second microorganism to transform the fingerprint spectrum of the first microorganism cultured under the first set of environmental factors to an expected fingerprint spectrum for the first microorganism under the second set of environmental factors that is compensated for drift due to the differences between the first and second sets of environmental factors that affect the metabolic state of the first microorganism.