This is a direct infusion-tandem mass spectrometry methodology utilizing a differential mobility system. This assay is performed on the SCIEX 5500 triple-quadrupole (QQQ) with a Shimadzu auto-sampler configured for direct infusion experiments, SelexION ion mobility device, and Shimadzu LC. This assay is built on the Sciex Lipidyzer Platform. We are using our in-house data analysis workflow and a combination of 70 lipid standards sourced from Sciex and Avanti Polar Lipids to provide accurate, quantitative measurements of over 1400 lipid species across 17 lipid subclasses within a biological sample. Download the excel file for a complete list of lipid species measured in this targeted assay.
This assay quantitatively measures the fatty acid and cholesterol composition of a biological sample. In Situ derivatization breaks up complex esterified lipids into constituent fatty acids and cholesterol, which can be measured by Gas Chromatography/Mass Spectrometer. The assay is performed on an Agilent 7890B/5977A GC-MS. The assay is compatible with stable isotope labeling. Data analysis utilizes the mathematical modeling-based isotopic spectral analysis (ISA) method to provide estimations of flux and lipid synthesis rates, as well as calculating the contribution of carbon sources to the Acetyl-CoA pool.