title: Self-association of zwitterionic polymer-lipid conjugates in water as examined by scattering measurements.
abstract: As a model of lipopeptide, a zwitterionic polymer-lipid conjugate was prepared from carboxymethylbetaine monomer (CMB) using a lipophilic initiator having a cholesteryl or dihexadecylglyceryl end group for atom transfer radical polymerization (ATRP). The polymer-lipid conjugates (Lipid-PCMB) obtained could be dispersed in water, and self-association of the compounds could be characterized by both light scattering (dynamic light scattering, DLS; electrophoretic light scattering, ELS) and small-angle X-ray scattering (SAXS). DLS and ELS measurements showed no secondary aggregation of the self-associated Lipid-PCMB molecules in salt solutions, though their surfaces were almost charge-balanced. The hydrophilic PCMB layer of Lipid-PCMB aggregates gave rise to dispersions under ionic conditions. Furthermore, structural analyses by DLS, ELS and SAXS measurements suggested that Lipid-PCMB aggregates consisted of a hydrophobic lipid core and a hydrophilic PCMB layer, that is, a core-shell structure. To the best our knowledge, this is the first study in which SAXS analyses were performed for zwitterionic polymer-lipid conjugates.
authors.affiliation: Department of Applied Chemistry, Graduate School of Science and Engineering, University of Toyama, Toyama, Japan.
authors.forename: Masanobu
authors.initials: M
authors.lastname: Murou
authors.forename: Hiromi
authors.initials: H
authors.lastname: Kitano
authors.forename: Masahiro
authors.initials: M
authors.lastname: Fujita
authors.forename: Mizuo
authors.initials: M
authors.lastname: Maeda
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Saruwatari
mesh_terms: D001622:Betaine / Q000031:analogs & derivatives* / Q000737:chemistry*; D055666:Lipopeptides / Q000138:chemical synthesis* / Q000737:chemistry*; D008567:Membranes, Artificial; D014867:Water / Q000737:chemistry*
chemical_list: D055666:Lipopeptides; D008567:Membranes, Artificial; D014867:Water; D001622:Betaine