Lipids quantitative analysis

Figure 10.9 shows the ehromatograms of fortified eoeonut oil obtained by using (a) normal-phase HPLC and (b) GPC/normal-phase HPLC. As ean be seen from these figures, ehemieal interferenees due to lipid material in the oil were eliminated by using the MD system that was used for quantitative analysis of all of the eom-pounds, exeept DL-a-toeopheryl aeetate, where the latter was eo-eluted with a triglieeride eompound and needed further separation. 

Miyoshi, H. Maeda, H. Tokutake, N. Fujita, T., Quantitative analysis of partition behavior of substituted phenols from aqueous phase into liposomes made of lecithin and various lipids, Bull. Chem. Soc. Jpn. 60, 4357-4362 (1987). 

To show some examples of the many cases of lipid paint materials reported in the literature, Table 7.3 reports the results of characteristic parameters obtained in the quantitative analysis of FAs in a series of samples (<1 mg) from paintings on various supports. 

Moreau RA, Whitaker BD and Hicks KB. 2002. Phytosterols, phytostanols, and their conjugates in foods structural diversity, quantitative analysis, and health-promoting uses. Prog Lipid Res 41 457-500. 

Costa CG, Struys EA, Bootsma A, et al (1997) Quantitative analysis of plasma acylcarnitines using gas chromatography chemical ionization mass fragmentography. J Lipid Res 38 173-182... 

Accurate determination of lipids in foods is required for nutritional labeling, certification, or for evaluation of standard of identity and uniformity, as well as examination of their effects on functional and nutritional properties of foods. Following lipid extraction and precise quantitative analysis, lipids so obtained may be used for analysis of other lipid characteristics and properties provided that nondestructive and mild extraction procedures are employed that retain the integrity of lipids. Thus, determination of lipid classes, fatty acid composition (unit du), and oxidative state of lipids (Chapter D2), amongst others, may be pursued following the extraction process. 

Ullman, M.D., McCluer, R.H. Quantitative analysis of plasma neutral glycosphingolipids by high performance liquid chromatography of their perbenzoyl derivatives. J. Lipid Res., 1977, 18, 371-377. 

Norlen, L. et al., A new HPLC-based method for the quantitative analysis of inner stratum corneum lipids in vivo with special reference to the free fatty acid fraction, Arch. Dermatol. Res., 290, 508, 1998. 

Akimoto, K., Yoshikawa, N., Higaki, Y., Kawashima, M., and Imokawa, G., Quantitative analysis of stratum corneum lipids in xerosis and asteatotic eczema, J. Dermatol., 20, 1-6, Jan. 1993. 

The methyl esters of the long-chain fatty acids can be subjected to exactly the same examination as outlined earlier in this chapter. In the usual case, these fatty acid esters will be composed largely of unsaturated (olefinic) linkages with little or no saturated components. This follows the pattern noted before for the substituents located at the C-2 position in other phosphoglycerides. A quantitative analysis of these fatty acids will show that there is 1 mol per mol of lipid phosphorus. The lysoalkenyletherphosphatidylcholine can then be studied further. 

Delacroix, H., Gulik-Krzywicki, T., and Seddon, J.M. (1996). Freeze fracture electronmicro-scopy of lyotropic lipid systems quantitative analysis of the inverse micellar cubic phase of space group Fd3m (Q227). J. Mol. Biol. 258, 88-103. 

Although tocopherols and tocotrienols can be detected by UV absorbance at 280 nm, fluorescence detection (excitation 294 nm and emission 326 nm), as shown in Figure 11.3, has proven to be a much more sensitive method. Electrochemical detection such as pulsed amperometric and coulometric (Uspitasari-Nienaber, 2002) has also proven to be sensitive and potentially valuable for the quantitative analysis of tocopherols and Tocotrienols (Abidi, 2000), especially for tocol analysis in blood and serum samples. HPLC mass detectors such as flame-ionization detectors, evaporative light-scattering detectors, and charged aerosol detectors have proven to be valuable for the quantitative analysis of many types of lipids, but because tocols have... 

Analytical methods for tocol analysis have continued to improve, as noted by Abidi (2000), and in the intervening ten years, as noted in this chapter. We predict that advances will continue to be made in the field of the chromatographic analysis of tocols. Also, we believe that lipidomic methods (quantitative analysis via direct injection tandem electrospray ionization mass spectrometry) will be developed for the rapid analysis of tocols, just as these methods have already been used for the profiling of phospholipids and glycolipids (Han, 2011 Welti, 2011). These methods usually involve the direct injection of lipid samples into a... 

As mentioned above, two different mass spectrometric approaches to lipid analysis exist The first one is performed directly from lipid extracts without prior chromatographic separation and is referred to as shotgun lipidomics. Here, lipid classes are separated in the ion source according to their intrinsic electrical properties (24). Detailed and unambiguous structural and quantitative analysis of individual species is obtained by means of multiplexed mass spectrometry using NL, PIS, and... 

Brtigger B, Erben G, Sandhoff R, Wieland FT, Lehmann WD. Quantitative analysis of biological membrane lipids at the low picomole level by nano electrospray ionization tandem mass spectrometry. Proc. Natl. Acad. Sci. U.S.A. 1997 94 2339-2344. 

Badings, H.T. De Jong, C. Glass capillary gas chromatography of fatty acid methyl esters. A study of conditions for the quantitative analysis of short- and long-chain fatty acids in lipids. J. Chromatogr. 1983, 279, 493-506. 

J2. Jones, D. C., Melchior, C. W., and Reeves, M. J. W., Quantitative analysis of individual bile acids by gas-liquid chromatography an improved method. ]. Lipid Res. 17,273-277... 

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