Abstract: Structure-activity methods based on molecular descriptors that are a combination of structural information about the through-space and through-bond relationships between components of a molecule's structure and spectral data attributable to those components are disclosed. In some embodiments, a molecule is described by multiple sets of such descriptors to account for flexibility in the structure of the molecule. In a particularly disclosed embodiment, predicted 13C—13C COSY data and 13C—13C distance data are used as descriptors. Models of molecular properties may be established using the disclosed spectral data-activity methods and used to predict the properties of molecules.

Abstract: Methods of compensating for drift in fingerprint spectra of microorganisms caused by changes in their environment are disclosed. These methods of compensating for drift permit identification of microorganisms from their fingerprint spectra regardless of the environment from which the microorganisms are obtained. Furthermore, the disclosed methods may be used to construct coherent databases of fingerprint spectra that may be expanded even though the standard database conditions are no longer experimentally achievable. In particular embodiments, methods of compensating for drift in pyrolysis mass spectra, constructing coherent pyrolysis mass spectral databases, and identifying bacteria from their pyrolysis mass spectra are disclosed.

Abstract: A food quality indicator device an indicator compound provided on a substrate. The indicator compound changes color due to the presence of volatile compounds, such as volatile bases, in spoiled food, even when the food is frozen. Alternatively, the indicator compound detects the presence of an unwanted amine-producing biological agent, such as bacteria or fungi. The indicator compound is typically contained within a polymeric matrix disposed on the substrate. Examples of suitable indicator compounds include halogenated azo dyes, sulfonated xanthene dyes, and sulfonated hydroxy-functional triphenylmethane dyes.