title: Synthesis of multiacyl poly(ethylene glycol) for the conjugation of cytochrome c to phospholipid vesicle.
abstract: To conjugate water-soluble macromolecules on the surface of phospholipid vesicles, we synthesized a poly(ethylene glycol) (PEG)-lipid having four acyl chains using a lysine (Lys)-type monodendron structure. One end of the diamino-PEG was amidified with Lys, and then two amino groups of the Lys moiety were amidified with two Lys derivatives which had been acylated with two stearoyl groups. The other end of the PEG was activated with a triazine group or a pyridyldithio group. The hydrate of the lipid mixture of dipalmitoylphosphatidylcholine, cholesterol, dipalmitoylphosphatidylglycerol, and the PEG-lipid at a molar ratio of 5/5/1/0.3 was extruded in order to prepare the phospholipid vesicles with the average diameter of 270 +/- 20 nm. The coupling ratio of cytochrome c with the PEG-lipid was monitored by HPLC, detecting the pyridyl 2-thione liberated from the pyridyldithio group and determining it to be 26% on the basis of the incorporated PEG-lipid.
authors.affiliation: Department of Polymer Chemistry, Advanced Research Institute for Science and Engineering, Waseda University, Tokyo 169-8555, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Ohkawa
authors.forename: Y
authors.initials: Y
authors.lastname: Teramura
authors.forename: S
authors.initials: S
authors.lastname: Takeoka
authors.forename: E
authors.initials: E
authors.lastname: Tsuchida
mesh_terms: D003574:Cytochrome c Group / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D010743:Phospholipids / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000138:chemical synthesis*
chemical_list: D003574:Cytochrome c Group; D010743:Phospholipids; D011092:Polyethylene Glycols