title: Quatsomes: vesicles formed by self-assembly of sterols and quaternary ammonium surfactants.
abstract: Thermodynamically stable nanovesicle structures are of high interest for academia and industry in a wide variety of application fields, ranging from preparation of nanomaterials to nanomedicine. Here, we show the ability of quaternary ammonium surfactants and sterols to self-assemble, forming stable amphiphilic bimolecular building-blocks with the appropriate structural characteristics to form in aqueous phases, closed bilayers, named quatsomes, with outstanding stability, with time and temperature. The molecular self-assembling of cholesterol and surfactant cetyltrimethylammonium bromide (CTAB) was studied by quasi-elastic light scattering, cryogenic transmission electron microscopy, turbidity (optical density) measurements, and molecular dynamic simulations with atomistic detail, upon varying the cholesterol-to-surfactant molar ratio. As pure species, CTAB forms micelles and insoluble cholesterol forms crystals in water. However, our molecular dynamic simulations reveal that the synergy between CTAB and cholesterol molecules makes them self-assemble into bimolecular amphiphiles and then into bilayers in the presence of water. These bilayers have the same structure of those formed by double-tailed unimolecular amphiphiles.
authors: Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Esfera UAB, Cerdanyola del Vallès, Spain.
authors: Lidia
authors: L
authors: Ferrer-Tasies
authors: Evelyn
authors: E
authors: Moreno-Calvo
authors: Mary
authors: M
authors: Cano-Sarabia
authors: Marcel
authors: M
authors: Aguilella-Arzo
authors: Angelina
authors: A
authors: Angelova
authors: Sylviane
authors: S
authors: Lesieur
authors: Susagna
authors: S
authors: Ricart
authors: Jordi
authors: J
authors: Faraudo
authors: Nora
authors: N
authors: Ventosa
authors: Jaume
authors: J
authors: Veciana
mesh_terms: D000077286:Cetrimonium; D002593:Cetrimonium Compounds / Q000737:chemistry*; D002784:Cholesterol / Q000737:chemistry*; D008051:Lipid Bilayers / Q000737:chemistry*; D008823:Micelles; D046529:Microscopy, Electron, Transmission; D056004:Molecular Dynamics Simulation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D013501:Surface-Active Agents / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics; D014867:Water
chemical_list: D002593:Cetrimonium Compounds; D008051:Lipid Bilayers; D008823:Micelles; D013501:Surface-Active Agents; D014867:Water; D002784:Cholesterol; D000077286:Cetrimonium