动脉微栓过滤器抗凝涂层修饰及生物相容性研究

A Study on Biocompatibility and Modification of Anticoagulant Coated Aterial Filter

为研制具有良好生物相容性的新型体外循环动脉微栓过滤器(AF),以化学接枝改性方法制备低分子肝素(LMWH)涂层、部分氧化的海藻酸钠(OSA)涂层的AF用涤纶滤网。利用红外光谱分析表面涂层基团,通过表面接触角测定、蛋白黏附试验、血小板黏附试验、抗凝活性检测、体外血栓形成试验等进行生物相容性评价,通过涂层动态脱落、管路压力、流量检测等评价滤器应用安全性能。结果显示,涂层后材料的红外光谱在涂层物吸收峰处出现变化,表面接触角变小(P<0.01),且OSA组(25.2±4.02)°小于LMWH组(32.7±4.65)°,人血清白蛋白黏附量、纤维蛋白原粘附量显著减少(P<0.05),OSA组黏附(1.63±0.37,1.32±0.14)μg/cm2少于LMWH组(2.56±0.81,2.00±0.32)μg/cm2,血浆接触涂层材料后PT、APTT显著延长,与PET组间差异有统计学意义(P<0.05)。模拟体外转流中约有10%的涂层物脱落,AF进口端压力、跨滤器压力差增加(P<0.01)、流量/转速减少。实验表明,化学接枝改性方法制备的LMWH及OSA涂层滤网,涂层结合稳定,生物相容性提高,满足应用安全需要。与LMWH涂层相比,OSA涂层的抗凝性能略差,但亲水性及对蛋白黏附的改善优于LMWH涂层,可能具有更好的组织相容性,加之OSA低廉的价格,将有更广泛的应用空间。

In order to develop novel aterial filter with excellent biocompatibility,we prepared dacron filter coated with low molecular weight heparin（LMWH） or partial oxidation sodium alginate（OSA）.The functional groups of the surface coating were determined with infrared spectroscopy.The biocompatibility was evaluated including contact angle,protein adhesion,in vitro platelet adhesion,coagulation indices,in vitro thrombosis.The safty was assessed by the loss of coating material,flow/roating speed,inlet and trans-filter pressure during analog circulation.There are similar changes in the infrared spectroscopy of coated material at the location of LMWH＇s or OSA＇s absorption peak.After being coated,the contact angle,albumin and fibrinogen adhering to the surface of dacron filter were decreased（P〈0.05）.For the LMWH coating,contact angle（32.7±4.65）°,albumin and fibrinogen adhered（2.56±0.81,1.63±0.37） μg/cm^2 were higher than that（25.2±4.02）°,（2.00±0.32,1.32±0.14）μg/cm^2 of OSA coating.The anticoagulant activity was notably promoted by coating,and dacron coated with LMWH was better than OSA（P〈0.05）.There was about 10% coating material loss in the analog circulation.The inlet and trans-filter pressure of coating filters was slightly increased,and flow/rotate was decreased.In conclusion,chemical graft-modification can be applied to the dacron filter.The biocompatibility of the coated materials is significantly promoted,and the safty meet the clinical demand.LMWH coating material has better hemocompatibility,while OSA coating material have better histocompatibility.For the carrier ability and low cost,OSA coating would get more development space.