Applications of Untargeted Chemical Analysis

Untargeted analysis refers to a method designed to capture as much information about a particular sample dimension, as possible. Different sample dimensions refer to classes of molecules, such as volatiles, lipids, proteins, metals, and metabolites, among others, that may be present in samples of interest. The sample preparation and analysis methods are designed to profile a particular sample dimension and provide a reproducible fingerprint. Such a fingerprint can be used to compare and potentially differentiate different sample types using a variety of data treatment strategies. Chemical features that differentiate between sample types (e.g., healthy vs. diseased) can be identified and used as markers for discrimination. Untargeted analysis often involves the use of techniques, like liquid chromatography coupled with high resolution mass spectrometry, so that complex mixtures can be resolved and features can be annotated with precise information. Different analysis techniques provide different levels of information and thus, different levels of confidence with respect to annotation of features. This talk will describe the use of untargeted analysis for various applications, including analysis and differentiation of beer types, effects of bacterial stressors, and natural products, specifically psilocybin mushrooms.