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Untargeted Lipidomics

Liquid chromatography (reversed phase) – Mass spectrometry-based untargeted lipidomics

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Analysis of lipids and lipophilic compounds in complex samples using high resolution mass spectrometers in untargeted manner results in detection of 1000-3000 features of which up to 600 and 550 can be identified (annotated) in animals and human serum respectively.

23 different lipids classes from internal database and LC-MS/MS annotation algorithm are detectable depending on the sample types.

Annotation is performed using metaSysX database which contains information about 1400 lipids. Samples are additionally measured in LC-MS/MS positive and negative ionization modes and are subjected to annotation using a fragmentation spectrum which increases the annotation level and results in the highest coverage of annotated lipids.

Measurements are performed in positive and negative ionization mode to increase the number of annotated compounds

Lipidomics (untargeted lipid profiling) - lipids are first extracted using organic solvent and subjected to measurement using reversed phase chromatography coupled to high resolution Thermo Fisher mass spectrometer of Orbi trap type. For reduction of the complexity of extracted lipids, a column with C8 stationary phase is used to separate the lipids and other lipophilic compounds based on their hydrophobicity. The differences in elution time enable detection and relative quantitation of bigger number of lipids of the same head groups or carbon chain.