Synthesis and AnticoagulantActivity of PolyureasContaining Sulfated Carbohydrates.

Polyurea-based synthetic glycopolymerscontaining sulfated glucose,mannose, glucosamine, or lactose as pendant groups have been synthesizedby step-growth polymerization of hexamethylene diisocyanate and correspondingsecondary diamines. The obtained polymers were characterized by gelpermeation chromatography, nuclear magnetic resonance spectroscopy,and Fourier transform infrared spectroscopy. The nonsulfated polymersshowed similar results to the commercially available biomaterial polyurethaneTECOFLEX in a platelet adhesion assay. The average degree of sulfationafter reaction with SO3was calculated from elemental analysisand found to be between three and four −OSO3groupsper saccharide. The blood-compatibility of the synthetic polymerswas measured using activated partial thromboplastin time, prothrombintime, thrombin time, anti-IIa, and anti-Xa assays. Activated partialthromboplastin time, prothrombin time, and thrombin time results indicatedthat the mannose and lactose based polymers had the highest anticoagulantactivities among all the sulfated polymers. The mechanism of actionof the polymers appears to be mediated via an anti-IIa pathway ratherthan an anti-Xa pathway. [ABSTRACT FROM AUTHOR]