This is a mass spectrometry-based approach that involves direct infusion of lipid samples into the AB SCIEX Lipidyzer Platform: a SCIEX 5500 triple-quadrupole (QQQ) with a Shimadzu auto-sampler configured for direct infusion experiments, SelexION ion mobility device, and Shimadzu LC. Backend analysis is performed using Sciex proprietary Lipidyzer software. When combined with SCIEX’s proprietary lipids standard sets, this instrument can provide accurate, quantitative measurements of over 1000 lipid species across 13 lipid classes within a biological sample.
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.