LC-MS-based method for the qualitative and quantitative analysis of complex lipid mixtures

ArticleinJournal of Lipid Research 47(4):804-14 · May 2006with53 Reads
DOI: 10.1194/jlr.M500506-JLR200 · Source: PubMed
Abstract
A simple and robust LC-MS-based methodology for the investigation of lipid mixtures is described, and its application to the analysis of human lipoprotein-associated lipids is demonstrated. After an optional initial fractionation on Silica 60, normal-phase HPLC-MS on a YMC PVA-Sil column is used first for class separation, followed by reversed-phase LC-MS or LC-tandem mass spectrometry using an Atlantis dC18 capillary column, and/or nanospray MS, to fully characterize the individual lipids. The methodology is applied here for the analysis of human apolipoprotein B-associated lipids. This approach allows for the determination of even low percentages of lipids of each molecular species and showed clear differences between lipids associated with apolipoprotein B-100-LDL isolated from a normal individual and those associated with a truncated version, apolipoprotein B-67-containing lipoproteins, isolated from a homozygote patient with familial hypobetalipoproteinemia. The methods described should be easily adaptable to most modern MS instrumentation.
    • "On the other hand, MS provides all information at the molecular species level, providing information on the chain length, degree of unsaturation and positional distribution of fatty acids at sn-1/sn-2 positions. The combination of HPLC with a mass spectrometer may result in a more detailed picture of particular lipid species within each class and of the whole lipidome in a single run [100]. 4.2.1. "
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    • "(GPC). Quantification of 16:0/18:1-GPC was according to a previous report [25] with some modifications. In brief, the analysis was performed on a Thermo Finnigan TSQ Quantum Ultra triple quadrupole mass spectrometer (ThermoFinnigan, San Jose, CA) in conjunction with a Thermo Dionex Ultimate 3000 LC and an electrospray source. "
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