title: Preparation of a stable phospholipid monolayer grafted onto a methacryloyl-terminated substrate as blood compatible materials.
abstract: We have prepared a surface-grafted phospholipid monolayer by in situ polymerization carried out at the interface between a pre-assembled phospholipid monolayer and a methacryloyl-terminated substrate. The phospholipid containing an acryloyl moiety, 1-stearoyl-2-[12-(acryloyloxy)-dodecanoyll-sn-glycero-3-phosphocholine (acryloyl-PC), was pre-assembled by vesicle fusion onto methacryloyl-terminated substrates which were silanized with 3-(trimethoxysilyl)propyl methacrylate (TSM). The acryloyl-PC monolayer and methacryloyl-terminated substrates were then polymerized in situ by adding a water-soluble initiator, 2,2-azobis(2-methylpropionamidine) dihydrochloride (AAPD), at 60 degrees C for 15 min. Atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) measurements indicated that the polymerized phospholipid surface on the TSM-silanized substrates formed a lipid monolayer structure with some defects. The polymerized phospholipid surfaces also showed good stability in methanol due to chemical bonding to solid surfaces. The grafting efficiency of acryloyl-PC monolayer on the TSM substrate, which was calculated by the relative carbon ratio of the polymerized acryloyl-PC monolayer on TSM substrate before and after methanol washing, was 94.5%. For comparative analysis, the acryloyl-PC monolayer was also polymerized onto dimethyl-terminated substrates silanized with dichlorodimethylsilane (DCM). In the absence of surface grafting moieties on solid substrates, the laterally polymerized acryloyl-PC monolayer physically adsorbed on substrates was easily removed in an organic solvent. The surface-grafted phospholipid monolayer was also greatly effective in the prevention of platelet adhesion.
authors.affiliation: Center for Biomaterials and Biotechnology, Department of Materials Science and Engineering, Kwangju Institute of Science and Technology, 1 Oryong-dong Puk-gu, Gwangju 500-712, South Korea.
authors.forename: Kwangmeyung
authors.initials: K
authors.lastname: Kim
authors.forename: Chulhee
authors.initials: C
authors.lastname: Kim
authors.forename: Youngro
authors.initials: Y
authors.lastname: Byun
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D001704:Biopolymers / Q000737:chemistry; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D008297:Male; D008689:Methacrylates / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D015394:Molecular Structure; D010743:Phospholipids / Q000737:chemistry*; D010973:Platelet Adhesiveness / Q000502:physiology*; D011817:Rabbits; D012821:Silanes / Q000737:chemistry; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D001704:Biopolymers; D020099:Coated Materials, Biocompatible; D008689:Methacrylates; D010743:Phospholipids; D012821:Silanes