Synthesis and blood compatibilities of novel segmented polyurethanes containing phosphatidylcholine analogous moieties i

  • PDF / 860,729 Bytes
  • 10 Pages / 612 x 792 pts (letter) Page_size
  • 100 Downloads / 175 Views

DOWNLOAD

REPORT


Welcome

MATERIALS RESEARCH

Comments

Help

Synthesis and blood compatibilities of novel segmented polyurethanes containing phosphatidylcholine analogous moieties in the main chains and long-chain alkyl groups in the side chains Arata Korematsu, Yu-Jun Li,a) Takayuki Murakami, and Tadao Nakayab) Department of Bioapplied Chemistry, Faculty of Engineering, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan (Received 14 December 1998; accepted 15 February 1999)

New segmented polyurethanes containing phospholipid moieties in the main chains and long-chain alkyl groups in the side chains were synthesized. The soft segments used in this study were poly(butadiene), poly(isoprene), hydrogenated poly(isoprene), and poly(1,6-hexyl-1,2-ethylcarbonate) diol. The hard segments of these polyurethanes were 4,4⬘-methylenediphenyl diisocyanate, bis[2-(2-hydroxyethyldimethylammonio)ethyl]2-cetyl1,3-propanediphosphate, and 1,4-butanediol. The blood compatibilities of the new polymers were evaluated by platelet-rich plasma contact studies and viewed by scanning electron microscopy using medical grade BioSpan威 and nonphospholipid polyurethane as references. These new materials have good surfaces in terms of platelet adhesion, and the morphology of adhered platelets undergoes a relatively low degree of variation. I. INTRODUCTION

Phospholipid consists of hydrophilic and hydrophobic groups and forms the lipid bilayer of plasma membranes.1 Phosphorylcholine, which is an electrically neutral and zwitterionic head group that represents the bulk of the phospholipid head groups present on the external surface of blood cells, is inert in coagulation assays.2 There is no doubt that the introduction of the phosphatidylcholine or its analogues into polymer is useful for improving blood compatibility.3,4 To obtain biocompatible polymers in artificial organs, in 1986 we successfully synthesized phospholipidlike diols and polyurethanes.5 Moreover, we investigated the properties of polymers containing phospholipid analogues in the main chains.6 Recently, new polyurethanes bearing phosphatidylcholine analogues in the main chains7–12 were synthesized in this laboratory. Our previous studies suggest that these new polyurethanes have excellent blood compatibilities but poor mechanical properties.3 To overcome this problem and further develop these new polyurethanes for practical biomedical application, we are trying to introduce some soft segments into our phospholipid modified polyurethanes. On the other hand, segmented polyurethanes (SPUs) most frequency used today in biomedical applications are a)

Present address: Procter & Gamble Far East Inc., 17 Koyo-cho Naka 1-chome, Higashinada-ku, Kobe 658-0032, Japan b) Address all correspondence to this author. e-mail: [email protected] J. Mater. Res., Vol. 14, No. 9, Sep 1999

http://journals.cambridge.org

Downloaded: 16 Mar 2015

poly(ether urethane)s that have good biostability,13–15 but they are subject to significant degradation under certain conditions of mechan