Plasmalogen extract

A so-called plasmalogen extract. This is a pool of extracted and derivatised erythrocyte samples. It is used solely to check for the detector response of the plasmalogens, thereby identifying active spots in the injection system. 

The fatty acid glycerol esters and the plasmalogens are transmethylated by adding methanolic HC1 to the sample and heating the mixture in a closed vial at 90°C for 4 h. After cooling the sample, the fatty acid methyl esters and the dimethylacetals are extracted with hexane. The concentrated hexane solution is ready for analysis by GC. 

Attempts to raise the plasmalogen levels in RCDP patients involve the administration of shark liver extracts, which may contain appreciable amounts of batyl alcohol, a 06 0 precursor. By doing this, the balance between the 06 0 and 08 0 plasmalogens will be perturbed. It is still unknown whether there is clinical efficacy from such treatment. 

Fig. 136. Isolation of neutral plasmalogens and alkyl diglycerides from the human perinephrium [181]. Adsorbent silica gel G solvent hexane-diethyl ether (99 + 5), double development times of run 40 min each visualisation carbonisation by heating with chromic acid/sulphuric acid, a lipid extract 6 first concentration stage c second concentration stage d third concentration stage e neutral plasmalogens / alkyl diglycerides...

A low-concentration of lithium chloride (e.g., 50 mM in aqueous phase) is preferable for lipid extraction for MDMS-SL since the lithium adduct of lipid species can yield unique and informative fragmentation patterns after CID (Part II). Moreover, the weakly acidic conditions resulted from a weak Lewis base of lithium ion and a strong Lewis acid of chloride could improve the extraction efficiency of anionic lipids to a certain degree and could lead to increased intrasource separation of molecular specie of anionic lipid classes from PE species in negative-ion ESI-MS (Chapter 3). Under such weakly acidic conditions, degradation of plasmalogen species does not occur. 

The lithium chloride solution in the extraction can be replaced with other salts such as ammonium acetate or a weak acid if necessary [33], However, an acidic environment may lead to plasmalogen degradation, thus it should be very cautious. It should be pointed out that although the aqueous phase is usually discarded after extraction, it could be used for analysis of many lipid classes, which largely disperse to it as reported [39],... 

The plasmalogens (0.2 to 2 mg) in diethyl ether (1.5 mL) are shaken vigorously for 2 min with cone, hydrochloric acid (1 mL). The ether layer is removed and the aqueous phase is extracted once more with ether (2 mL) and once with hexane (2 mL). The combined extracts are washed with distilled water before the solvent is evaporated in a stream of nitrogen. The free aldehydes are obtained by preparative TLC on silica gel G layers, with hexane-diethyl ether (90 10, v/v) as the mobile phase. Aldehydes migrate to just below the solvent front, and they can be recovered from the adsorbent for further... 

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