Comprehensive blood plasma lipidomics by liquid chromatography/quadrupole time-of-flight mass spectrometry

A comparison of five lipid extraction solvent systems for lipidomic studies of human LDL

“…LDL particles are known carriers of FFAs, which in our study were found to be predominantly stearoyl chains (18:0); these may be involved in the formation and stabilization of the lipid droplet, as recently reported for PLA 2 -modifi ed LDL particles ( 54 ). Lyso-phospholipids are also known components of LDL ( 23 ) and plasma ( 44,45 ), and may increase as result of oxidative damage ( 55 ). CS species even though they have been previously reported in LDL ( 56 ) and at a submicromolar concentration range in the plasma ( 57 ), their localization within the particle remains uncertain.…”

“…In tissues, etherPEs have been suggested to act as antioxidants by chelating cupric ions and protecting other PLs from oxidation ( 52,53 ), but their function in LDL is as yet unknown. The major PI species detected in this study was 18:0/20:4 PI ( m/z 885.5489), which agrees with the PI composition of plasma ( 44,45 ). Glycosylated lipids, such as LacCer and Statistical analysis of data set 1 and data set 2 was performed using the ASCA model with test permutations (details in supplementary data online).…”

“…In fact, the number of individual lipid species present is likely to be higher than suggested by the numbers identifi ed in this study, as the identifi cation is based on the accurate m/z value of the ion, and only the total number of carbons and double bonds can be determined, so isomers with different carbon chain lengths in acyl and in ether-linked phospholipids are not distinguished. Interestingly, glycero-PSs were not identifi ed in the LDL extracts, despite the fact that they have previously been identifi ed in plasma (44)(45)(46), suggesting that they could be confi ned to other lipoproteins. The absence of PSs in LDL may not be surprising given that they are generally only localized in the for extraction of the predominant lipid classes, there were striking differences in the extraction of minor lipid classes.…”

Psoralen and Ultraviolet A Light Treatment Directly Affects Phosphatidylinositol 3-Kinase Signal Transduction by Altering Plasma Membrane Packing

“…Analysis of (Phospho)lipids-Lipid analysis was based on high resolution liquid chromatography coupled to high resolution quadruple time-of-flight (TOF) mass spectrometry (51,52). For lipidomics analyses, a 1290 Infinity LC system (Agilent Technologies, Waldbronn, Germany) was used.…”

A novel stop-flow two-dimensional liquid chromatography–mass spectrometry method for lipid analysis

“…Under the conditions of normal phase (NP) LC and hydrophilic interaction liquid chromatography (HILIC), lipids are separated according to their polar head groups [16][17][18][19]. Lipids with different aliphatic chains can be resolved by reversed-phase (RP) LC analysis [20][21][22][23]. Nevertheless, one-dimensional chromatographic separation may not be satisfactory for complex lipids analysis.…”