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A series of heparinized hydrophilic polymers (H-RSD) composed of a hydrophobic element, a nonionic hydrophilic element, a cationic element and ionically bound heparin was synthesized. The permeability of the H-RSD polymers with various chemical compositions and water contents was investigated. From the studies on the permeability, it has been found that in order to maintain good permeability after heparinization, the nonionic hydrophilic element is necessary. In addition, the microencapsulation of activated charcoal granules using a H-RSD polymer with a similar permeability to that of Cuprophan was examined. In vitro adsorption studies and in vivo direct hemoperfusion studies on the activated charcoal microencapsulated with the H-RSD polymer, show that the H-RSD coating prevents clot formation without loss of the absorption power of the activated charcoal.

The change in aggregability of the platelets stored in the storage tube fabricated from a newly developed heparinized hydrophilic polymer (H-RSD) has been studied in comparison with plasticized poly(vinyl chloride) (PVC) which is widely used for blood bags. Rabbit blood was directly withdrawn into the storage tube containing an anticoagulant from the carotid. Then the tube was mechanically sealed with screw cocks and centrifugated to prepare platelet-rich plasma (PRP) in the tube and again mechanically clamped to separate the PRP from the residual precipitate. The PRP was stored in situ in the storage tube at room temperature under agitation. During storage, the change in the aggregability of the PRP induced by adenosine diphosphate (ADP) was studied and the morphological change in the platelets adhered onto the inner surface of the storage tube was observed by scanning electron microscopy. In the H-RSD tube, the aggregability was maintained during two-day storage, while in the PVC tube, the aggregability was completely lost after one-day storage. The scanning electron microscopic studies demonstrated that the reduction in the aggregability of the stored platelets is closely correlated with the morphological deformation of the platelets adhered onto the surface of the storage tube.