Iwasaki Y, Ishihara K, Nakabayashi N, Khang G, Jeon J H, Lee J W, Lee H B
Institute for Medical and Dental Engineering, Tokyo Medical and Dental University, Japan.
J Biomater Sci Polym Ed. 1998;9(8):801-16. doi: 10.1163/156856298x00163.
We have synthesized omega-methacryloyloxyalkyl phosphorylcholine (MAPC) polymers as new blood-compatible materials, with attention to the surface structure of the biomembrane and investigated their blood compatibility. The blood compatibility observed on the MAPC polymers is due to their strong affinity to phospholipids. When the blood comes in contact with the MAPC polymer, phospholipids in the plasma preferentially adsorb on the surface, compared with the plasma proteins or cells. The adsorbed phospholipids construct a biomembrane-like structure on the MAPC polymer surface. The MAPC polymers then have an excellent blood compatibility. In this study, we prepared a gradient poly(MAPC)-grafted polyethylene (PE) surface using a corona discharge treatment method to clarify the effect of the chemical structure of the MAPC unit on the blood compatibility of the MAPC polymers. The surface composition of MAPC and the hydrophilicity on the poly(MAPC)-grafted PE surface were determined by X-ray photoelectron spectroscopic (XPS) analysis and contact angle measurement with water, respectively. The phosphorus/carbon (P/C) ratio determined by the XPS analysis increased, but the water contact angle decreased with increasing corona irradiation energy. These results indicated that the surface density of the MAPC unit was increased. More than 2.5 cm from the starting point of the corona irradiation, the P/C ratio and water contact angle of the surface achieved a constant level. Thus, the surface was completely covered with the grafted poly(MAPC) chain. The effect of the methylene chain length of the MAPC unit on surface properties was also observed. The phospholipid polar group of the MAPC unit was effectively exposed on the surface as the chain length became longer. Moreover, the hydrophobicity of the surface was increased with the increase in the methylene chain length of the MAPC unit. The number of platelets adhering to the poly(MAPC)-grafted PE surface was reduced from the same point where the P/C ratio became constant.
我们合成了ω-甲基丙烯酰氧基烷基磷酰胆碱（MAPC）聚合物作为新型血液相容性材料，关注生物膜的表面结构并研究了它们的血液相容性。在MAPC聚合物上观察到的血液相容性归因于它们对磷脂的强亲和力。当血液与MAPC聚合物接触时，与血浆蛋白或细胞相比，血浆中的磷脂优先吸附在表面。吸附的磷脂在MAPC聚合物表面构建了类似生物膜的结构。然后，MAPC聚合物具有优异的血液相容性。在本研究中，我们使用电晕放电处理方法制备了梯度聚（MAPC）接枝聚乙烯（PE）表面，以阐明MAPC单元的化学结构对MAPC聚合物血液相容性的影响。通过X射线光电子能谱（XPS）分析和用水进行接触角测量，分别测定了聚（MAPC）接枝PE表面上MAPC的表面组成和亲水性。通过XPS分析确定的磷/碳（P/C）比增加，但随着电晕辐照能量的增加，水接触角减小。这些结果表明MAPC单元的表面密度增加。在距电晕辐照起点超过2.5厘米处，表面的P/C比和水接触角达到恒定水平。因此，表面完全被接枝的聚（MAPC）链覆盖。还观察到了MAPC单元的亚甲基链长度对表面性质的影响。随着链长度变长，MAPC单元的磷脂极性基团有效地暴露在表面上。此外，随着MAPC单元亚甲基链长度的增加，表面的疏水性增加。在P/C比变得恒定的同一点，聚（MAPC）接枝PE表面上粘附的血小板数量减少。
