Lipids analysis by liquid chromatography

Pajkovic, N. van Breemen, R. 2005. Analysis of carotenoids using atmospheric pressure chemical ionization mass spectrometry. In Modem Methods for Lipid Analysis by Liquid Chromatography (Byrdwell, C., Ed.). AOCS Publishing, Champaign, IL, pp. 413 30. 

Hsu, E.-E. and Turk, J. (2005) Electrospray ionization with low-energy collisionally activated dissociation tandem mass spectrometry of complex lipids Structural characterization and mechaiusm of fragmentation. In Modern Methods for Lipid Analysis by Liquid Chromatography/Mass Spectrometry and Related Techiuques (Byrdwell, W.C., ed.). pp. 61-178, AOCS Press, Champaign, IL. 

Kostiainen, R. Kauppila, T. J. Analysis of steroids by liquid chromatography—Atmospheric pressure photoionization mass spectrometry. In Byrdwell, W. C. (Ed.), Modern Methods For Lipid Analysis By Liquid Chromatography/Mass Spectrometry And Related Techniques, AOCS Press Champaign, IL, 2005, pp. 472-487. 

Lee SH, Oe T, Arora JS, Blair lA. Analysis of Fe-II-mediated decomposition of a linoleic acid-derived lipid hydroperoxide by liquid chromatography/mass spectrometry. J Mass Spectrom. 2005b 40 661—668. 

Li, N., Shaw, A.R., Zhang, N.,Mak,A. andLi, L.(2004)Lipidraftproteomics analysis of in-solution digest of sodium dodecyl sulfate-solubilized lipid raft proteins by liquid chromatography-matrix-assisted laser desorption/ionization tandem mass spectrometry. Proteomics 4, 3156-3166. 

Hennion, M.C., J.C. Thieblement, R. Rosset, P. Scribe, J.C. Marty, and A. Saliot. 1983. Rapid semi-preparative class separation of organic compounds from marine lipid extracts by high-performance liquid chromatography and subsequent quantitative analysis by gas chromatography. J. Chromatogr. 280 351-362. 

In recent years, HPLC coupled with ESI-MS has become a well-established method for the identification and detection of chemical stmctures of lipids, including sphingolipids. Recently, Sugawara and coworkers [44] identified the chemical structures of glucosylceramides from maize, rice, mushroom, and sea cucumber by liquid chromatography-ion trap mass spectrometry with an ESI interface. In the positive full-scan mode, [M-t-HJ" ", [M-l-H—H2O ] , or [M-l-H—162]" (loss of glucose) was used for MS/MS analysis to obtain the product ions, which were used for the identification of the glucocerebrosides. 

The separation of intact polar lipids by liquid chromatography (LC) and the subsequent detection by mass spectrometry (MS) has today become straightforward. LC-MS is no longer a sophisticated technique only in the hands of specialists. Today, it is a routinely used, although advanced, analytical technique. The fields of application are expanding and today the use of LC-MS with electrospray (ES) ionization grows at the expense of other ionization techniques, at least where analysis of intact polar lipids is concerned. 

The content of this chapter focuses on the analysis of intact polar lipids by high-pressure liquid chromatography (HPLC) with flow or loop injection -and mass spectrometry (MS) or tandem mass spectrometry (MS-MS) using thermospray (TS), discharge-assisted TS [or plasmaspray (PSP)], electrospray (ES) and atmospheric pressure chemical ionization (APCI). It was intended to include only those papers describing the analysis of intact polar lipids by liquid chromatography on-line with MS. However, many papers describe flow or loop injection with MS and/or the analysis of derivatives of polar lipids. These papers, describing excellent applications of MS and/or MS-MS of polar lipids, are included since this chapter would not have been complete without them. 

Giuffrida, F., Destaillats, F., Skibsted, L.H. andDionisi, F. Structural analysis of hydroperoxy-and epoxy-triacylglycerols by liquid chromatography mass spectrometry. Chem. Phys. Lipids 131,41 9 (2004). 

Cajka T, Fiehn O. Comprehensive analysis of lipids in biological systems by liquid chromatography-mass spectrometry. Trends Anal Chem. 2014 61 192-206. 

High performance liquid chromatography (HPLC) has been by far the most important method for separating chlorophylls. Open column chromatography and thin layer chromatography are still used for clean-up procedures to isolate and separate carotenoids and other lipids from chlorophylls and for preparative applications, but both are losing importance for analytical purposes due to their low resolution and have been replaced by more effective techniques like solid phase, supercritical fluid extraction and counter current chromatography. The whole analysis should be as brief as possible, since each additional step is a potential source of epimers and allomers. 

The purity of all lipids and anthracyclines exceeded 98% based on thin-layer chromatography (TLC) and/or high-performance liquid chromatography (HPLC) analysis, performed as described by Barenholz and coworkers (38,49,50). 

Chlorella sorokiniana var. pacificensis were treated with 180 ppm O3 for 50 min in autotrophic media. Lipids were extracted by using Chloroform/methanol and prepared for gas-liquid chromatography (GLC) as described by Frederick and Heath (24). The average % concentration of fatty acids were calculated from 3 GLC runs in 5 separate samples. The O3/O2 column refers to ratios of average % concentration and represents standard deviation. Confidence Level was calculated by least squares analysis. 

Fig. 4.5.2 Actual strategies for CDG diagnosis. Initial investigations on CDG patients are routinely carried out by isoelectric focusing (IEF) of serum transferrin. With a CDG type I pattern, subsequent analysis should imply determination of phosphomannomutase (PMM) and phos-phomannose isomerase (PMI) activities. Further studies, like analysis of the lipid-linked- and protein-bound-oligosaccharides, determination of enzyme or sugar transporter activities and molecular biology studies often have to be performed in more specialised laboratories. HPLC High-performance liquid chromatography, TLC thin-layer chromatography...

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