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
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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    • "Further, it may not be neglected that other ionization techniques such as chemical ionization or atmospheric pressure chemical ionization could be more sensitive to specific lipids. Modern approaches to lipidomic analysis are dominated by MS (Want, Cravatt, & Siuzdak, 2005), usually preceded by separation by LC (Sommer, Herscovitz, Welty, & Costello, 2006) or GC ( Jiye et al., 2005). New MS-based lipidomics methods allow the study of intact lipid molecular species from very small amounts of samples ( Schwudke et al., 2006), e.g., from cultured neural cells or (micro)regions dissected from brain. "
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