Plasma lipid matrix

TVurin, V.A. and Gorbunov, N.V. (1984). The study of state of lipid matrix of plasma membranes of synaptosomes of brain in gorbusha during migration from sea to river (In Russian). Zhumal Evolutsionnoy Biokhimii i Physiologii 20,341-345. 

Little JL, Wempe MF, Buchanan CM (2006) Liquid chromatography-mass spectrometry/mass spectrometry method development for drug metabolism studies examining lipid matrix ionization effects in plasma. J Chromatogr B 833 219-230... 

The current opinion, widely held, is that all biological membranes, including mammalian plasma membranes, have as a structural framework a phospholipid bilayer of which the characteristic feature is a parallel array of hydrocarbon chains, averaging 16 carbon atoms in length. This bilayer has some of the properties of a two-dimensional fluid in which individual lipid molecules can diffuse rapidly in the plane of their own monolayer, but cannot easily pass into the other monolayer. This lipid matrix provides the basic structure of the membrane. Whereas some protein molecules cover part of the membrane, particularly its outer surface, other protein strands penetrate the lipid layer, every here and there, and some of these strands are bunched together to form water-filled tubes or pores (Wallach and Zahler, 1966). These proteins are responsible for most of the membrane s functions, e.g. receiving and transduc-... 

Stiibiger, G., Pittenauer, E., Belgacem, O., Rehulka, P, Widhalm, K., and Allmaier, G. 2009. Analysis of human plasma lipids and soybean lecithin by means of high-performance thin-layer ehromatography and matrix-assisted laser desorption/ionization mass speetrometry. Rapid Commun. Mass Spectrom., 23 2711-2723. 

Ylinen et al. [53] developed an ion-pair extraction procedure employing tetrabutylamonium (TBA) counter ions for determination of PFOA in plasma and urine in combination with gas chromatography (GC) and flame ionisation detection (FID). Later on, Hansen et al. [35] improved the sensitivity of the ion-pair extraction approach using methyl tertiary butyl ether (MTBE) and by the inclusion of a filtration step to remove solids from the extract making it amenable to liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) determination. Ion-pair extraction procedure has been the basis of several procedures for biota [49,54-58] and food samples [50,59,60]. However, this method has shown to have some limitations, such as (1) co-extraction of lipids and other matrix constituents and the absence of a clean-up step to overcome the effects of matrix compounds and (2) the wide variety of recoveries observed, typically ranging. 

The major polymers that make up the wall are polysaccharides and lignin. These occur together with more minor but very important constituents such as protein and lipid. Water constitutes a major and very important material of young, primary walls (2). The lignin is transported in the form of its building units (these may be present as glucosides) and is polymerized within the wall. Those polysaccharides which make up the matrix of the wall (hemicelluloses and pectin material) are polymerized in the endomembrane system and are secreted in a preformed condition to the outside of the cell. Further modifications of the polysaccharides (such as acetylation) may occur within the wall after deposition. Cellulose is polymerized at the cell surface by a complex enzyme system transported to the plasma membrane (3). 

Fig. 4. An apoptotic peripheral blood eosinophil observed under EM. The apoptotic cell displays the characteristic condensation of nuclear chromatin into large, electron-dense masses surrounding the central, relatively electron-lucent nuclear matrix. The swelling and breakage of plasma and perinuclear membranes and the release of the contents of granules from swollen, enlarged, electron-lucent granule containers within secretory cells are also observed. A single osmiophilic lipid body is found in the cytoplasm (x 18,500) (D6). Reproduced with permission from Dvorak, A. M., Images in clinical medicine, an apoptotic eosinophil. N. Engl. J. Med. 340, 437 (1999).

Reviews appeared on the following subjects Analysis of lipid hydroperoxides , the difficulties encountered for hydroperoxide analysis in a plasma matrix , post-column derivatization after GLC of lipid hydroperoxides and methods for detection and characterization of hydroperoxy groups in oxidized polyolefins . 

Biological samples (plasma, serum, blood, and urine) are very complex. They contain a wide variety of matrix components such as proteins, lipids, and salts. To quantify trace amount of analytes (e.g., drug and its metabolites) in complex biological samples by liquid chromatography-mass spectrometry (LC-MS), the samples should be properly treated prior to being injected onto an LC-MS instrument,... 

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