18194-24-6Relevant articles and documents
Chain Order in Lipid Bilayers: FTIR and Solid State NMR Studies on Bilayer Membranes from 1,2-Dimyristoyl-sn-glycero-3-phosphoglucose
Wolfangel, Peter,Müller, Klaus
, p. 9918 - 9928 (2003)
Multilamellar dispersions from a new synthetic phospholipid, 1,2-dimyristoyl-sn-glycero-3-phosphoglucose (DMPGE), bearing a glucose ring in the polar headgroup, are studied by means of FTIR, 2H, and 31P NMR spectroscopy. The investigations are focused on the evaluation of the molecular ordering of the lipid molecules as a function of temperature and cholesterol content. Information about the conformational order of the acyl chains is obtained from variable temperature FTIR investigations. Analysis of the CH2 stretching and wagging modes of nondeuterated compounds provides the relative changes in conformational order in the vicinity of the main transition and integral values of distinct gauche conformers over the whole acyl chains, respectively. Likewise, CD2 rocking bands are used to derive the amount of gauche conformers at a specific chain segment in samples containing selectively deuterated acyl chains. The present work represents the first report where the orientational order parameter simultaneously is obtained via two independent procedures. The first method is based on the combination of the CD2 rocking band data with those from complementary 2H NMR studies. The second procedure refers to a line shape analysis of variable temperature 31P NMR spectra. A comparison of the available data for the present lipids with those from related systems, such as 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), reveals a minor influence of the glucose headgroup on the (overall) orientational order while some effect is registered for the conformational order of the lipid molecules. In summary, the present work demonstrates the future potential of such combined FTIR and solid-state NMR studies in order to get detailed information of the lipid ordering in phospholipid bilayers. As shown here, such techniques are of general help in order to separate orientational and segmental (conformational) order in disordered alkyl chains, as there is no restriction to lipid systems as examined in the present work.
Method for preparing difatty acyl phosphatidylcholine by solid-phase reaction
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Paragraph 0023; 0024, (2019/12/25)
The invention relates to a method for preparing difatty acyl phosphatidylcholine by a solid-phase reaction. Glycerol phosphatidylcholine is subjected to wet-process loading by using a high-activity solid adsorbent, and then a condensation reaction is carried out on the glycerol phosphatidylcholine with fatty acid to obtain the difatty acyl phosphatidylcholine. The method comprises the following steps: dissolving glyceryl phosphatidylcholine in an organic solvent, adding a high-activity solid adsorbent, carrying out adsorbing dispersion while stirring, removing the organic solvent by vacuum evaporation, and carrying out vacuum drying on the obtained solid-phase loaded mixed material; dissolving fatty acid in an organic solvent, adding a condensation coupling agent, carrying out heating reflux to prepare active ester of fatty acid, adding the solid-phase loaded glyceryl phosphatidylcholine, and continuing reflux to prepare a difatty acyl phosphatidylcholine crude product; and carrying out filtering to recover the high-activity solid adsorbent, desolventizing mother liquor, pulping a crude product by using an organic solvent, and carrying out recrystallizing to obtain the high-puritydifatty acyl phosphatidylcholine. According to the method, the reaction yield reaches 65% or above, the product purity reaches 99% or above, the process is simple, the production period is short, andindustrial production is easy to achieve.
Allylamine-containing liposomes
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, (2008/06/13)
The invention concerns liposomal preparations comprising as the active agent a compound of formula I in free base form or in acid addition salt form. It also concerns a method of preparation of such liposomal preparations by encapsulating a compound of formula I with an appropriate liposome forming material, a corresponding pharmaceutical compositions, and methods of treatment of systemic, topical and pulmonal fungal infections.
