title: Cryogenic electron microscopy study of nanoemulsion formation from microemulsions.
abstract: We examine a process of preparing oil-in-water nanoemulsions by quenching (diluting and cooling) precursor microemulsions made with nonionic surfactants and a cosurfactant. The precursor microemulsion structure is varied by changing the concentration of the cosurfactant. Water-continuous microemulsions produce initial nanoemulsion structures that are small and simple, mostly unilamellar vesicles, but microemulsions that are not water-continuous produce initial nanoemulsion structures that are larger and multilamellar. Examination of these structures by cryo-electron microscopy supports the hypothesis that they are initially vesicular structures formed via lamellar intermediate structures, and that if the lamellar structures are too well ordered they fail to produce small simple structures.
authors.affiliation: Department of Chemical Engineering and Materials Science , University of Minnesota , Minneapolis, Minnesota 55455, United States.
authors.forename: Han Seung
authors.initials: HS
authors.lastname: Lee
authors.forename: Eric D
authors.initials: ED
authors.lastname: Morrison
authors.forename: Chris D
authors.initials: CD
authors.lastname: Frethem
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Zasadzinski
authors.forename: Alon V
authors.initials: AV
authors.lastname: McCormick
mesh_terms: D020285:Cryoelectron Microscopy; D004655:Emulsions / Q000737:chemistry; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry*; D009821:Oils / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties; D014867:Water / Q000737:chemistry*
chemical_list: D004655:Emulsions; D009821:Oils; D014867:Water