Lipid, analysis

Christie WW Lipid Analysis, 2nded. Pergamon Press, 1982. 

Lipid Screening. The problems of lipid analysis in the newborn is difficult because of the fact that most methods for analysis for lipids require substantial amounts of serum, yet a total lipid determination is very important in various types of disease. This problem can be solved by thin-layer chromatography (59). Figure 38 shows a typical pattern obtained when an extract 7rom 10 microliters of serum is subjected to thin-layer chromatography. If these specimens are scanned, and an internal standard is run, one can obtain a rough approximation of the distribution of the various lipids in the serum. This is shown in Figure 39, in which a normal specimen is run in an adult. 

Christie, W.W., Lipids their structure and occurrence, in Lipid Analysis, Isolation, Separation, Identification and Structural Analysis of Lipids, Vol. 5, Christie, W.W., Ed., The Oily Press, England, 2003, pp. 3-33. 

The results for bacterial whole-cell analysis described here establish the utility of MALDI-FTMS for mass spectral analysis of whole-cell bacteria and (potentially) more complex single-celled organisms. The use of MALDI-measured accurate mass values combined with mass defect plots is rapid, accurate, and simpler in sample preparation then conventional liquid chromatographic methods for bacterial lipid analysis. Intact cell MALDI-FTMS bacterial lipid characterization complements the use of proteomics profiling by mass spectrometry because it relies on accurate mass measurements of chemical species that are not subject to posttranslational modification or proteolytic degradation. 

Volume 432. Lipidomics and Bioactive Lipids Mass-Spectrometry—Based Lipid Analysis (in preparation)... 

K. Kimpe, C. Drybrooms, E. Schrevens, P. A. Jacobs, R. Degeest and M. Waelkens, Assessing the relationship between form and use of different kinds of pottery from the archaeological site Sagalassos (southwest Turkey) with lipid analysis, Journal of Archaeological Science, 31, 1503 1510(2004). 

There are a huge number of applications of GC/MS to lipid analysis in cultural heritage reported in the literature. Lipid characterization, together with the study of lipid degradation processes, is an important research area in conservation science [1 31]. 

Evershed, R.P. (1992a). Gas chromatography of lipids. In Lipid Analysis A Practical Approach, ed. Hamilton, R.J. and Hamilton, S., IRL Press, Oxford, pp. 113-151. 

Christie, W. W., Dobson, G., and Shepherd, T. (1999). Laboratory accreditation in a lipid analysis context. Lipid Technology 11 118-119. 

Contamination is a major problem in lipid analysis and the use of plastic containers and stoppers, rubber bungs or tubing, and any grease on stopcocks, etc., must be avoided. All solvents used should be of the purest grade and be peroxide-free and all glassware should be scrupulously clean. 

Gas-liquid chromatography is a very useful technique in lipid analysis, particularly for the separation of very similar compounds within classes. Because of the wide variations in structure and properties between classes it is not usually possible to resolve members of different classes on the same column. GLC is useful for both quantitative and qualitative analysis and also in the investigation of lipid structure. 

HPLC has been applied to lipid analysis mainly in consideration of the necessity to avoid high temperatures, so at the very beginning, its applications dealt with thermally unstable molecules (e.g., tocopherols, phenolics, oxidation products) and often it was used as an ancillary technique, as a preparative step prior to MS analysis. The limits were in the high volume of the HPLC band that strongly limited the possibility to transfer it to a GC or to a MS. Only in the last 20 years or somewhat less, this kind of hyphenation has become commercially available. 

Several F-labeled fatty acid derivatives have been successfully prepared and evaluated as potential FAO assessing tracers [19-24]. Methyl-branched-chain (w- F-fluorofatty acids, such as 3-methyl-(3-MFHA) and 5-methyl-17-[ F]fluoro-heptadecanoic acid (5-MFHA), have been reported [23]. In a comparative study, it was found that rw-[ F]fluoropalmitic acid (FPA) exhibits the highest myocardial uptake, followed by 5-MFHA and 3-MFHA. FPA possesses the fastest myocardial washout rate, and 3-MFHA the slowest. In lipid analysis studies, 5-MFHA... 

Yeung J, Yu TF. Effects of isoflavones (soy phyto-estrogens) on serum lipids analysis of randomized controlled trials. Nutr. J. 2, 15, 2003. 

A newer approach for lipid analysis is electrospray ionization tandem mass spectrometry (ESI-MS/MS) (Welti et al., 2002). This method requires limited sample preparation and sample size to identify and quantify lipids. Fauconnier et al. (2003) used ESI-MS/MS to analyze phospholipid and galactolipid levels during aging of potato tubers. 

Odutuga, A. A., Prout, R. E. S. Lipid analysis of human enamel and dentine. Arch, oral Biol. 19, 729 (1974)... 

Perres, N., Sajdera, S. W., Anderson, N. G Lipid analysis of vesicles isolated from the matrix of calcifying cartilage. Fed. Proc. 30, 1244 (1971)... 

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