Mayuri P V, Bhatt Anugya, Joseph Roy, Ramesh P
Polymer Processing Laboratory, Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Satelmond Palace Campus, Trivandrum 695012, India.
Thrombosis Research Unit, Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Satelmond Palace Campus, Trivandrum 695012, India.
Mater Sci Eng C Mater Biol Appl. 2016 Mar;60:19-29. doi: 10.1016/j.msec.2015.11.004. Epub 2015 Nov 10.
Poly(ethylene-co-vinyl alcohol) (EVAL) has been recommended as a material suitable for blood contacting applications. Effect of ethylene content and associated hydrophobicity of EVAL on the blood-material interactions have been documented in the literature. In this work, surface chemistry of EVAL substrate was altered by photografting a hydrophilic monomer, 2-hydroxyethyl acrylate (HEA) with the aid of a photoinitiator, benzophenone (BP), and the effect of surface modification on the blood-material interactions was investigated. Since the modified material was intended to be used as leukodepletion filters, a solution containing EVAL, HEA and BP was electrospun into fibroporous mats and UV treated to induce grafting. Degree of grafting, bonding between fibers and fiber diameter increased with increase in UV exposure time whereas mechanical properties showed a decreasing trend. Decreased water contact angle indicated improved wetting characteristics. In vitro hemocompatibility tests revealed that the modified EVAL surface exhibited significantly lower hemolytic activity, protein adsorption and platelet adhesion than neat EVAL. The modification did not have any substantial effect on the activation of the complement system and coagulation parameters. Photografting led to significant reduction in the adhesion of red blood cells (RBC) whereas white blood cell (WBC) consumption remained above 90%. The results implied that photografting HEA on EVAL substantially improves hemocompatibility of EVAL and when it is used as a filter, it selectively removes leukocytes and allows easy passage of other blood components.
聚乙烯 - 乙烯醇共聚物（EVAL）已被推荐作为一种适用于血液接触应用的材料。EVAL的乙烯含量及其相关疏水性对血液 - 材料相互作用的影响已在文献中有所记载。在本研究中，借助光引发剂二苯甲酮（BP），通过光接枝亲水性单体丙烯酸2 - 羟乙酯（HEA）来改变EVAL基材的表面化学性质，并研究表面改性对血液 - 材料相互作用的影响。由于改性材料旨在用作白细胞去除过滤器，将含有EVAL、HEA和BP的溶液电纺成纤维多孔垫并进行紫外线处理以诱导接枝。接枝度、纤维间的结合力以及纤维直径随紫外线照射时间的增加而增加，而机械性能呈下降趋势。水接触角的减小表明润湿性得到改善。体外血液相容性测试表明，改性后的EVAL表面比纯EVAL表现出显著更低的溶血活性、蛋白质吸附和血小板粘附。这种改性对补体系统的激活和凝血参数没有任何实质性影响。光接枝导致红细胞（RBC）的粘附显著减少，而白细胞（WBC）的消耗率仍保持在90%以上。结果表明，在EVAL上光接枝HEA可显著提高EVAL的血液相容性，并且当用作过滤器时，它能选择性地去除白细胞并使其他血液成分易于通过。
