title: Quantitative characterization of the lipid encapsulation of quantum dots for biomedical applications.
abstract: The water solubilization of nanoparticles is key for many applications in biomedicine. Despite the importance of surface functionalization, progress has been largely empirical and very few systematic studies have been performed. Here we report on the water solubilization of quantum dots using lipid encapsulation. We systematically evaluate the monodispersity, zeta potential, stability, and quantum yield for quantum dots encapsulated with single and double acyl-chain lipids, pegylated double acyl-chain lipids, and single alkyl-chain surfactant molecules with charged head groups. We show that charged surfactants and pegylated lipids are important to obtain monodisperse suspensions with high yield and excellent long-term stability.
  
  
  BACKGROUND
  This study reports on solubilization of nanoparticles in water, a key, but often neglected aspect for biomedical applications. The authors demonstrate that charged surfactants and PEGylated lipids are important to obtain monodisperse suspensions with high yield and long-term stability.
authors.affiliation: Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland, USA.
authors.forename: Justin F
authors.initials: JF
authors.lastname: Galloway
authors.forename: Alan
authors.initials: A
authors.lastname: Winter
authors.forename: Kwan Hyi
authors.initials: KH
authors.lastname: Lee
authors.forename: Jea Ho
authors.initials: JH
authors.lastname: Park
authors.forename: Charlene M
authors.initials: CM
authors.lastname: Dvoracek
authors.forename: Peter
authors.initials: P
authors.lastname: Devreotes
authors.forename: Peter C
authors.initials: PC
authors.lastname: Searson
mesh_terms: D008055:Lipids / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D045663:Quantum Dots; D012995:Solubility; D013501:Surface-Active Agents / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D008055:Lipids; D013501:Surface-Active Agents; D014867:Water; D011092:Polyethylene Glycols