title: Water-soluble pegylated quantum dots: from a composite hexagonal phase to isolated micelles.
abstract: We present a simple method based on the dispersion of fluorescent quantum dots (QD) into a liquid crystal phase that provides either nanostructured material or isolated QD micelles depending on water concentration. The liquid-crystal phase was obtained by using a gallate amphiphile with a poly(ethylene glycol) chain as the polar headgroup, named I. The hydration of QD/I mixtures resulted in the formation of a composite hexagonal phase identified by small-angle X-ray scattering and by polarized light and fluorescence optical microscopy, showing a homogeneous distribution of fluorescence within hexagonal phase. This composite mesophase can be converted into isolated QD-I micelles by dilution in water. The fluorescent QD-I micelles, purified by size exclusion chromatography, are well monodisperse with a hydrodynamic diameter of 20-30 nm. Moreover, these QD do not show any nonspecific adsorption on lipid or cell membranes. By simply adjusting the water content, the PEG gallate amphiphile I provides a simple method to prepare a self-organized composite phase or pegylated water soluble QD micelles for biological applications.
authors.affiliation: Université de Rennes 1, Sciences Chimiques de Rennes, CNRS UMR 6226, Campus de Beaulieu, F-35042 Rennes Cedex, France.
authors.forename: F
authors.initials: F
authors.lastname: Boulmedais
authors.forename: P
authors.initials: P
authors.lastname: Bauchat
authors.forename: M J
authors.initials: MJ
authors.lastname: Brienne
authors.forename: I
authors.initials: I
authors.lastname: Arnal
authors.forename: F
authors.initials: F
authors.lastname: Artzner
authors.forename: T
authors.initials: T
authors.lastname: Gacoin
authors.forename: M
authors.initials: M
authors.lastname: Dahan
authors.forename: V
authors.initials: V
authors.lastname: Marchi-Artzner
mesh_terms: D004583:Electrons; D008055:Lipids / Q000737:chemistry; D008823:Micelles; D046529:Microscopy, Electron, Transmission; D015394:Molecular Structure; D011092:Polyethylene Glycols / Q000737:chemistry*; D045663:Quantum Dots; D012995:Solubility; D013057:Spectrum Analysis; D014867:Water / Q000737:chemistry*
chemical_list: D008055:Lipids; D008823:Micelles; D014867:Water; D011092:Polyethylene Glycols