Discovery—General Metabolites and Lipidomics
The overall workflow for the discovery workflow is shown above. Generally, sample preparation entails the removal of protein extraction of metabolites. The exact details depend on the types of metabolites being examined. For example, lipids are extracted using a more nonpolar solvent. The metabolites typically are separated by high-Pressure Liquid Chromatography (HPLC). The type of chromatography used will depend on the metabolites of interest. Standard reverse phase (C18) chromatography is used most of the time. For more hydrophilic compounds, HILIC (hydrophilic Interaction Chromatography) can be used. Alternatively, for more lipophilic compounds RF C30 columns can be used. Mass spectrometry can be performed in either positive or negative mode. See Discovery Metabolomics for more detail.
Currently, the core has developed a targeted metabolomics/lipidomics method for over 130 compounds. Additional metabolites can be added based on the investigator's needs. This is similar to the above "Discovery Metabolomics and Lipidomics" described above except the analysis focuses on a subset of known metabolites. This can be modified to customers' needs.
One option for targeted metabolomics is to use the AbsoluteIDQ® p400 HR Kit. This kit provides the standards and software to quantify over 400 metabolites. This approach is similar to our metabolomic workflows above except the samples are provided as a kit and special software is utilized. Similar to above, the processed metabolites are analyzed by LC-MS/MS using our QE HF mass spectrometer. This provides an extensive set of metabolites but is not adaptable to the customer's needs. In addition, it is more costly and samples must be processed in sets (approx. 70 samples/experiment).