Sevastianov V I, Eberhart R C, Kim S W
Biomaterials Laboratory, Institute of Transplantology and Artificial Organs, Moscow, USSR.
ASAIO Trans. 1988 Jan-Mar;34(1):10-8.
The authors studied the surface structure of organosiloxane-polyether urethane co-polymer films cast against low and high surface free energy materials (glass/ceramic and metal). A novel surface interaction parameter, the gold nucleus density distribution (GND), determined by partial gold decoration transmission electron microscopy, was used to indirectly assess the dispersive contribution to interfacial surface free energy. A water wetting assay was used to characterize the hydrophobic/hydrophilic balance of the polymer film surfaces. Two biological interaction parameters, one involving the kinetics of albumin and fibrinogen adsorption from plasma and the other a platelet adhesion index (RIPA), were used to estimate blood compatibility. Results indicate that mold properties influence the surface structure of this block co-polymer, sequestering polysiloxane groups at mold, and possibly air interfacial regions of the film. However, as shown by ESCA and FTIR analysis, specific chemical groups did not correlate with the blood compatibility indices. The GND correlate with initial albumin and fibrinogen adsorption rates. Initial protein adsorption was less well predicted by surface water wettability. Neither surface structure nor surface interaction data predicted later (60-120 min) protein sorption or platelet adhesion. Subsequent events may be influenced by protein turnover and cell-surface interactions, and are less influenced by polymer surface properties.
作者研究了浇铸在低表面自由能材料（玻璃/陶瓷）和高表面自由能材料（金属）上的有机硅氧烷 - 聚醚聚氨酯共聚物薄膜的表面结构。通过部分金修饰透射电子显微镜测定的一种新型表面相互作用参数——金核密度分布（GND），被用于间接评估对界面表面自由能的分散贡献。用水润湿性测定法来表征聚合物薄膜表面的疏水/亲水平衡。使用两个生物相互作用参数，一个涉及血浆中白蛋白和纤维蛋白原吸附的动力学，另一个是血小板粘附指数（RIPA），来评估血液相容性。结果表明，模具性质会影响这种嵌段共聚物的表面结构，使聚硅氧烷基团在模具以及薄膜可能的空气界面区域聚集。然而，正如X射线光电子能谱（ESCA）和傅里叶变换红外光谱（FTIR）分析所示，特定化学基团与血液相容性指标并无关联。GND与初始白蛋白和纤维蛋白原吸附速率相关。表面水润湿性对初始蛋白质吸附的预测效果较差。表面结构和表面相互作用数据均无法预测后期（60 - 120分钟）的蛋白质吸附或血小板粘附情况。后续事件可能受蛋白质周转和细胞 - 表面相互作用的影响，而受聚合物表面性质的影响较小。
