title: Importance of a biofouling-resistant phospholipid polymer to create a heparinized blood-compatible surface.
abstract: Heparinization is believed to be one of the methods to suppress thrombus formation on blood-contacting surfaces. However, this study hypothesizes that heparinization alone might not be sufficient to provide a blood-compatible surface; that is, a surface property that resists biofouling is necessary to obtain an effective heparin-modified surface. 2-Methacryloyloxyethyl phosphorylcholine (MPC) polymers with 2-aminoethyl methacrylate (AEMA) were synthesized to immobilize heparin through ionic bonding. The primary amino groups of AEMA were considered to be the polymer surface because the zeta-potential of the surface was positive when the mole fraction of the AEMA units was above 0.2. The antithrombogenic character of the polymer surface modified with heparin was evaluated by both Lee-White and microsphere column methods. The coagulation period of human whole blood in the absence of anticoagulant in glass tubing coated with the MPC polymer was longer than that in the original glass tube. Cell adhesion was completely inhibited on the MPC polymer surface after contact with human whole blood without anticoagulant. However, many adherent blood cells were observed on poly(2-ethylhexyl methacrylate-co-AEMA) (no MPC unit) even after heparinization. These results strongly indicate that the MPC polymer is a useful substrate where the heparin works well and that the heparin-immobilized MPC polymer has superior blood compatibility to the simple MPC polymer.
authors.affiliation: Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Japan. yasu.org@tmd.ac.jp
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Iwasaki
authors.forename: Naoya
authors.initials: N
authors.lastname: Shibata
authors.forename: Madoka
authors.initials: M
authors.lastname: Ninomiya
authors.forename: Kimio
authors.initials: K
authors.lastname: Kurita
authors.forename: Nobuo
authors.initials: N
authors.lastname: Nakabayash
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Ishihara
mesh_terms: D000925:Anticoagulants / Q000494:pharmacology; D001769:Blood / Q000187:drug effects*; D001777:Blood Coagulation / Q000187:drug effects; D001798:Blood Proteins / Q000032:analysis / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis* / Q000494:pharmacology; D006493:Heparin / Q000494:pharmacology; D006801:Humans; D008689:Methacrylates; D010743:Phospholipids; D010767:Phosphorylcholine / Q000031:analogs & derivatives*; D011108:Polymers / Q000138:chemical synthesis* / Q000494:pharmacology; D055672:Static Electricity; D013499:Surface Properties
chemical_list: D000925:Anticoagulants; D001798:Blood Proteins; D020099:Coated Materials, Biocompatible; D008689:Methacrylates; D010743:Phospholipids; D011108:Polymers; D010767:Phosphorylcholine; C070638:2-methacryloyloxyethyl phosphorylcholine; C072703:2-aminoethylmethacrylate; D006493:Heparin