title: Acid-triggered release via dePEGylation of DOPE liposomes containing acid-labile vinyl ether PEG-lipids.
abstract: Four structurally related, acid-labile polyethylene glycol (PEG) conjugated vinyl ether lipids have been synthesized and used at low molar ratios to stabilize the nonlamellar, highly fusogenic lipid, dioleoylphosphatidyl ethanolamine, as unilamellar liposomes. Acid-catalyzed hydrolysis of the vinyl ether bond destabilized these liposomes by removal of the sterically-stabilizing PEG layer, thereby promoting contents release on the hours timescale at pH<5. Structure-property correlations of these compounds suggested that single vinyl ether linkages between the PEG headgroup and the lipid backbone produce faster leakage rates. These studies also suggested that the presence of a slight negative charge at the membrane surface can accelerate the acid-catalyzed leakage process.
authors.affiliation: Department of Chemistry, 560 Oval Drive, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Junhwa
authors.initials: J
authors.lastname: Shin
authors.forename: Pochi
authors.initials: P
authors.lastname: Shum
authors.forename: David H
authors.initials: DH
authors.lastname: Thompson
mesh_terms: D000143:Acids; D005452:Fluoresceins / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D008055:Lipids / Q000737:chemistry*; D008081:Liposomes; D009682:Magnetic Resonance Spectroscopy; D010714:Phosphatidylethanolamines / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D014753:Vinyl Compounds / Q000737:chemistry*
chemical_list: D000143:Acids; D005452:Fluoresceins; D007202:Indicators and Reagents; D008055:Lipids; D008081:Liposomes; D010714:Phosphatidylethanolamines; D014753:Vinyl Compounds; C094877:dioleoyl phosphatidylethanolamine; C100195:vinyl ether; D011092:Polyethylene Glycols; C007740:fluorexon