Yoshishige Murata

Antithrombogenic Poly(vinyl chloride) with Heparin- and/or Prostaglandin I2-Immobilized in Hydrogels:

Poly(vinyl chloride) (PVC) with heparin- and/or prostaglandin I2 (PGI2)- immobilized on crosslinked polyacrylamide hydrogels were prepared by the ad dition of the dry hydrogels to a PVC tetrahydrofuran solution. Immobilized heparin was found to be continuously released from the PVC matrix at 37 ° C in a physiological saline. Antithrombogenic activity of PVCs with heparin and/or PGI2 was evaluated by activated partial thromboplastin time (aPTT), whole blood clotting time, and inhibition of platelet aggregation. The heparin- immobilized PVCs exhibited excellent anticoagulant activity and the PGI2 immobilized PVCs completely inhibit platelet aggregation of human blood after sitting for 46 h in a physiological saline.

Surface characterization of poly(styrene-co- fluoroalkylfumarate): XPS and contact angle measurement study

We studied styrene and fluoroalkylfumarate (FAF) copolymers and their surfaces by means of contact angle measurement and X-ray photoelectron spectroscopy (XPS). The surfaces of the copolymers were very hydrophobic (even with a small amount of FAF) because of the concentration of FAF segments at the surface. The hydrolyzed surfaces of the copolymers became slightly hydrophilic compared to the as cast. The XPS data suggested that the fluoroalkyl groups seemed to be primarily hydrolyzed. The surfaces with a large amount of FAF changed their characteristics to hydrophobic again under atmospheric conditions. This phenomenon was due to the inversion of the carboxyl and the fluoroalkyl groups. These hydrolyzed surfaces seemed to be useful for modifying polymer surfaces by attaching to other functional molecules.