title: Cationic triple-chain amphiphiles facilitate vesicle fusion compared to double-chain or single-chain analogues.
abstract: Cationic, triple-chain amphiphiles promote vesicle fusion more than structurally related double-chain or single-chain analogues. Two types of vesicle fusion experiments were conducted, mixing of oppositely charged vesicles and acid-triggered self-fusion of vesicles composed of cationic amphiphile and anionic cholesteryl hemisuccinate (CHEMS). Vesicle fusion was monitored by standard fluorescence assays for intermembrane lipid mixing, aqueous contents mixing and leakage. Differential scanning calorimetry was used to show that triple-chain amphiphiles lower the lamellar-inverse hexagonal (L(alpha)-H(II)) phase transition temperature for dipalmitoleoylphosphatidylethanolamine. The triple-chain amphiphiles may enhance vesicle fusion because they can stabilize the inversely curved membrane surfaces of the fusion intermediates, however, other factors such as extended conformation, packing defects, chain motion, or surface dehydration may also contribute. From the perspective of drug delivery, the results suggest that vesicles containing cationic, triple-chain amphiphiles (and cationic, cone-shaped amphiphiles in general) may be effective as fusogenic delivery capsules.
authors.affiliation: Department of Chemistry and Biochemistry, and the Walther Cancer Research Center, University of Notre Dame, Notre Dame, IN 46556-5670, USA.
authors.forename: Atanas V
authors.initials: AV
authors.lastname: Koulov
authors.forename: Lauri
authors.initials: L
authors.lastname: Vares
authors.forename: Mahim
authors.initials: M
authors.lastname: Jain
authors.forename: Bradley D
authors.initials: BD
authors.lastname: Smith
mesh_terms: D009327:4-Chloro-7-nitrobenzofurazan; D002152:Calorimetry, Differential Scanning; D002412:Cations; D016503:Drug Delivery Systems; D005456:Fluorescent Dyes; D018014:Gene Transfer Techniques; D006863:Hydrogen-Ion Concentration; D008051:Lipid Bilayers; D008561:Membrane Fusion; D008968:Molecular Conformation; D010712:Phosphatidic Acids / Q000737:chemistry* / Q000494:pharmacology; D010713:Phosphatidylcholines / Q000737:chemistry* / Q000494:pharmacology; D010714:Phosphatidylethanolamines / Q000737:chemistry* / Q000494:pharmacology; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology*; D012235:Rhodamines; D013696:Temperature
chemical_list: D002412:Cations; D005456:Fluorescent Dyes; D008051:Lipid Bilayers; D010712:Phosphatidic Acids; D010713:Phosphatidylcholines; D010714:Phosphatidylethanolamines; D000644:Quaternary Ammonium Compounds; D012235:Rhodamines; D009327:4-Chloro-7-nitrobenzofurazan; C029773:rhodamine B