Synthesis and non-thrombogenicity of heparinoid polyurethaneureas

Unsaturated polyurethaneureas were synthesized from 4,4'-diphenylmethane diisocyanate, 1,2-diaminopropane and polybutadiene containing hydroxyl groups at both ends of a chain. The polyurethaneureas were cast as a film and subsequently treated with N-chlorosulphonyl isocyanate to produce sulphamate and carboxylate groups on the film surface. The level of in vitro non-thrombogenicity increased with increasing degree of modification. The high blood compatibility is attributed to the low level of platelet stimulation and to heparinoid activity. It was observed that platelet stimulation depends on the surface structure of the original polyurethaneura, and that the heparinoid activity is related with the presence of sulphamate and carboxylate groups.