Lin J C, Cooper S L
Department of Chemical Engineering, University of Wisconsin--Madison 53706, USA.
Biomaterials. 1995 Sep;16(13):1017-23. doi: 10.1016/0142-9612(95)94910-d.
The development of a small diameter artificial vascular graft or prosthesis is limited by rapid thrombus formation and subsequent embolization upon blood contact. Plasma surface modification was employed to modify the inner surface of small diameter low density polyethylene (LDPE) tubing without varying the outer surface chemistry and physical properties of the tubing. A sulphur dioxide (SO2) plasma was used to form sulphonate functionality on the surface. In addition, a hexamethyldisiloxane (HMDSO) plasma and different gas flow ratios of SO2-HMDSO gas mixture plasmas were used to form ultrathin polysiloxane-like coatings inside the LDPE tubing. X-ray photoelectron spectroscopy (XPS) indicated that the inner surface of the tubing can be modified uniformly with this treatment. In addition, XPS results showed that the percentage of sulphur atoms bound to two or three oxygen atoms (sulphone or sulphonate) increased with the SO2-HMDSO mass flow rate ratio. The blood compatibility of the plasma-modified model materials was evaluated using an ex vivo canine arteriovenous shunt model. Similar thrombogenicity was observed comparing the untreated control and the surfaces modified by HMDSO plasma and SO2-HMDSO gas mixture plasmas, despite the differences in surface chemistry. The SO2 plasma-modified surface, which is the most hydrophilic as measured by the captive bubble contact angle measurement technique, was more thrombogenic than the untreated control. This may be attributed to the combined effect of the surface chemistry and surface hydrophilicity.
小直径人工血管移植物或假体的发展受到血液接触时快速血栓形成及随后栓塞的限制。采用等离子体表面改性来修饰小直径低密度聚乙烯（LDPE）管材的内表面，而不改变管材的外表面化学性质和物理性质。使用二氧化硫（SO2）等离子体在表面形成磺酸酯官能团。此外，使用六甲基二硅氧烷（HMDSO）等离子体以及SO2 - HMDSO气体混合等离子体的不同气体流量比，在LDPE管材内部形成超薄的聚硅氧烷类涂层。X射线光电子能谱（XPS）表明，通过这种处理管材的内表面能够被均匀改性。此外，XPS结果显示，与两个或三个氧原子结合的硫原子（砜或磺酸酯）的百分比随着SO2 - HMDSO质量流量比的增加而增加。使用体外犬动静脉分流模型评估了等离子体改性模型材料的血液相容性。尽管表面化学性质存在差异，但比较未处理的对照以及由HMDSO等离子体和SO2 - HMDSO气体混合等离子体改性的表面时，观察到了相似的血栓形成倾向。通过俘获气泡接触角测量技术测得，SO2等离子体改性表面是最亲水的，但它比未处理的对照更易形成血栓。这可能归因于表面化学性质和表面亲水性的综合作用。
