Lipidomics applications

Murphy, S. A. and A. Nicolaou 2013. Lipidomics applications in health, disease and nutrition research. Mol Nutr Fond Res 57(8) 1336-1346. 

Alkaline Adducts PE species can essentially form adducts with any alkaline (e.g., Li, Na, K) ion in the positive-ion mode when a modifier carrying the alkaline ion is added to the hpid solution, but sodium adduct is formed if no other alkaline ion is added. Similar to the formation of proton adducts, the ionization efficiency of PE alkaline adducfs is much lower in comparison to that of PC counterparts. Therefore, utilization of these adducts for analysis of PE species present in biological samples is suppressed by PC species by shotgun lipidomics. Application of these adducts for the analysis of PE species with LC-MS is also minimal. 

It should be recognized that following the same line of reasoning, low-energy MS analysis has also been used to identify the location of double bond(s) of TAG [7] and glycerophospholipids [9]. However, this type of work currently belongs more to the research laboratory than to the practical lipidomics application. 

C. Application of Targeted Lipidomics for the Study of Endocannabinoid Metabolism... 

Wolf, C. and Quinn, P.J., Lipidomics Practical aspects and applications, Progr Lipid Res, 2007, in press. 

Development and application of novel analytical methods in lipidomics... 

Shevchenko and colleagues have developed a somewhat different form of shotgun lipidomics which is particularly suitable to applications utilizing a hybrid linear ion trap (LIT) Fourier transform (FT) instrument, for example, LTQ-Orbitrap, called top-down lipidomics [18,24]. In a top-down lipidomics experiment, the survey scan is recorded at high resolution (100,000) (full width at half maximum height [FWMH]) in the FT analyzer. Mass accuracy on FT instruments is typically <5 ppm and often with internal calibration <2 ppm. This degree of mass accuracy... 

The present overview briefly considers the more successful applications of the individual methodologies in lipid analyses, the improvements brought about by their complementary combinations, along with the progress toward further resolution and more sensitive analyses. The overview concludes with a brief consideration of the lipid analyses demanded by lipidomics, and recent developments in proteonomics and genomics. 

Revisions in Chapter 7 are related to the increased interest in lipid analysis, notably boosted by introduction of the new omics field-lipidomics-and by developments of MS imaging as a robust new application of MALDI-MS. In addition, novel potentials of lipid analysis in applications of the direct desorption from solid surfaces and MALDl-MS imaging to diagnostics using Upids as disease markers are described. 

Fuchs, B. and Schiller, 1. 2009. Application of MALDI-TOF mass spectrometry in lipidomics, Eur J. Lipid Sci. TechnoL, 111 83-98. 

MALDI-MS is generally performed at (complex) lipids mixtures, although post-LC-column fractionation systems have been developed as well. Additionally, MALDI-MS imaging of TLC plates is useful technology in Upid analysis [219]. The application of MALDI-MS in lipid analysis and lipidomics has been extensively reviewed [193, 194, 220, 221]. The most widely applied matrices in lipid analysis are DHB and 2,6-dihydroxyacetophenone (DHAP). Unlike in ESI-MS, MALDI-MS provides positive-ion response for all phospholipid classes. Individual components may be observed as [M+H]+, [M+Na], [M+K]+, or adduct ions with additional HWa - or H+/K+-exchange, thus significantly complicating the interpretation and (relative) quantification of individual components in... 

Li M, Yang L, Bai Y, Liu H. Analytical methods in lipidomics and their applications. Anal Chem. 2014 86 161-75. 

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