区域选择性改性的纤维素和壳聚糖衍生物及其血液相容性

通过对纤维素和壳聚糖的区域选择性改性，将内皮细胞表面硫酸乙酰肝素（ES—HS）分子结构中对其血液相容性有重要影响的官能团引入纤维素和壳聚糖的分子结构中，并将其通过离子键固定在部分阳离子化的纤维素膜上，以期模拟ES—HS的血液相容性。血小板吸附结果表明，6位改性的纤维素衍生物的吸附程度较高。在五种壳聚糖衍生物中，2位的NS03／NAc为6／4的衍生物表现出最低的血小板吸附。当保持壳聚糖2位的NS03／NAc值不变时，对6位进行完全磺酸酯化，也可有效减少血小板的吸附。

Regioselectively modified cellulose and chitosan derivatives and their blood compatibility

In order to simulate the blood compatibility of endothelial cell surface heparansulfate （ES- HS）, different functional groups in ES-HS, which play a great role in blood compatibility, have been re- gioselectively introduced into the molecules of cellulose and chitosan with variable degree of substitution （DS）. These modified cellulose and chitosan derivatives were immobilized on partially cationized cellu- lose membranes via polyelectrolyte complexes formation. The platelet adhesion properties of the deriva- tives modified membranes have been tested in vitro. The results showed that cellulose derivatives modified at 6-position had higher platelet adhesion. Among the modified five chitosan derivatives, the one with a value of 6/4 of NSO3/NAc at 2-position showed the lowest platelet adhesion. The platelet adhesion de- creased clearly after introducing 6-O-sulfo groups into chitosan derivative at a same ratio of NSO3/NAc （6/4）.