Skarja G A, Brash J L
Department of Chemical Engineering, McMaster University, Hamilton, Ontario, Canada.
J Biomed Mater Res. 1997 Mar 15;34(4):439-55. doi: 10.1002/(sici)1097-4636(19970315)34:4<439::aid-jbm5>3.0.co;2-l.
The adhesion of platelets to a series of segmented polyurethanes having sulfonate groups in the hard segment is reported. The polyurethanes were synthesized using sulfonated chain extenders of different structure. Analogous control materials without sulfonate groups also were studied. Adhesion was measured in vitro using washed human platelets in a carrier fluid consisting of Tyrode's buffer with apyrase, albumin, and red cells at normal concentration. The polymers were characterized by gel permeation chromatography and elemental analysis. Water absorption and thermal transitions also were determined. It was found that the sulfonated materials absorb significant amounts of water while the nonsulfonated analogs do not. The surfaces of polymer films were characterized by water contact angle and XPS. The contact angles of the sulfonated surfaces were relatively low. Platelet adhesion to the sulfonated polymers was found to be very high compared to the nonsulfonate analogs. The local environment of the sulfonate groups (different chain extenders) also appears to have an effect on platelet interactions. Albumin adsorption was high on all the materials and was not correlated with platelet adhesion. It appears from this work that platelets may have a binding site that is specific for sulfonate groups.
报道了血小板与一系列在硬段含有磺酸基团的嵌段聚氨酯的黏附情况。这些聚氨酯是使用不同结构的磺化扩链剂合成的。还研究了不含磺酸基团的类似对照材料。在体外，使用洗涤过的人血小板，在由含有腺苷三磷酸双磷酸酶、白蛋白和正常浓度红细胞的台氏缓冲液组成的载液中测量黏附情况。通过凝胶渗透色谱法和元素分析对聚合物进行表征。还测定了吸水率和热转变情况。发现磺化材料吸收大量水分，而非磺化类似物则不吸收。通过水接触角和X射线光电子能谱对聚合物薄膜表面进行表征。磺化表面的接触角相对较低。与非磺化类似物相比，发现血小板对磺化聚合物的黏附非常高。磺酸基团的局部环境（不同的扩链剂）似乎也对血小板相互作用有影响。白蛋白在所有材料上的吸附都很高，且与血小板黏附无关。从这项工作来看，血小板可能有一个对磺酸基团特异的结合位点。
