title: Impact of mechanism of formation on encapsulation in block copolymer vesicles.
abstract: Vesicles prepared from block copolymers have been mooted for the encapsulation of water-soluble molecules. This is because the membranes of polymer vesicles have been shown to be more stable than those in vesicles formed from lipids, with the membrane properties being tuned by the length and nature of the hydrophobic block in the polymer. The generally accepted mechanisms of vesicle formation involve either wrap-up of a lamellar sheet or formation via a sequence of micelle to worm to disks to vesicles. These should lead to efficient encapsulation. Alternatively, a method involving phase separation followed by re-structuring has been recently suggested. Here, we show that this final mechanism holds for vesicles formed from a PEO-b-PDEAMA copolymer by a pH switch and that this mechanism leads to highly inefficient encapsulation on vesicle formation.
authors.affiliation: Unilever Corporate Research, Colworth, Sharnbrook, Bedford, MK44 1LQ, United Kingdom. d.j.adams@liverpool.ac.uk
authors.forename: Dave J
authors.initials: DJ
authors.lastname: Adams
authors.forename: Sarah
authors.initials: S
authors.lastname: Adams
authors.forename: Derek
authors.initials: D
authors.lastname: Atkins
authors.forename: Michael F
authors.initials: MF
authors.lastname: Butler
authors.forename: Steve
authors.initials: S
authors.lastname: Furzeland
mesh_terms: D000465:Algorithms; D002850:Chromatography, Gel; D020285:Cryoelectron Microscopy; D004337:Drug Carriers / Q000138:chemical synthesis / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008027:Light; D008689:Methacrylates / Q000737:chemistry; D053769:Nanocapsules / Q000737:chemistry* / Q000648:ultrastructure; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D012235:Rhodamines / Q000737:chemistry; D012256:Riboflavin / Q000737:chemistry; D012542:Scattering, Radiation
chemical_list: D004337:Drug Carriers; D005456:Fluorescent Dyes; D008689:Methacrylates; D053769:Nanocapsules; D011108:Polymers; D012235:Rhodamines; D011092:Polyethylene Glycols; C029773:rhodamine B; C519537:diethylaminoethyl methacrylate; D012256:Riboflavin