Aggregate formation in the intercalation of long-chain fatty acid esters into liposomes
作者:Yael Cohen、Michal Afri、Aryeh A. Frimer
DOI:10.1016/j.chemphyslip.2008.07.005
日期:2008.10
Various hydrophobic benzenediacetic esters, the corresponding benzenedipropionic esters, and branched alkyl esters were intercalated into DMPC liposomes, where the molar ratio (n/n) of ester:DMPC was 1:5. In the case of the very long-chain derivatives, double carbonyl peaks were observed in the C-13 NMR spectrum. This doubling phenomenon was observed only for the carbonyl peaks, whose chemical shift is most sensitive to solvent polarity. and disappeared when the ester:DMPC molar ratio drops below 1:15. This doubling reflects the presence of two populations in these samples: one group includes those molecules which are intercalated within the liposome and feel the polarity corresponding to the liposomal microenvironment; the other consists of aggregates of these long-chain derivatives located in the extra-liposomal aqueous phase. (C) 2008 Elsevier Ireland Ltd. All rights reserved.