EFFECT OF POLYOL TYPE ON THE PHYSICAL-PROPERTIES AND THROMBOGENICITY OF SULFONATE-CONTAINING POLYURETHANES

Polyetherurethanes (PEUs) based on polytetramethylene oxide (PTMO) as the polyol, and derivatized with propyl sulfonate functionality, have previously been shown to possess antithrombotic properties. In this ar ticle, the bulk physical properties of sulfonated and nonsulfonated po lyurethanes containing either polyethylene oxide (PEO) or PTMO as the soft segment are studied. The in vitro shape-change Of platelets in co ntact with these surfaces, and their ex vivo blood-contacting response are also investigated. It was found that PEO-base was physically weak er than PTMO-base, which is attributed to a lower degree or phase sepa ration in the former. In the dry state, sulfonation enhanced the- phys ical properties for PTMO-containing polyurethane (PTMO-SO3-0.20), but weakened the PEO-containing polyurethane (PEO-SO3-0.15). In vitro plat elet spreading studies showed the lowest degree of platelet spreading and also the lowest platelet density on PEO-base, while platelet sprea ding and density on the other three materials and polyethylene (PE) wa s greater. The thromboresistance of these materials was evaluated usin g a canine arteriovenous series shunt ex vivo. It was determined that PTMO-SO3-0.20 was the least thrombogenic, followed by both PEO-base an d PEO-SO3-0.15, and that PTMO-base was the most thrombogenic. (C) 1993 John Wiley & Sons, Inc.