Nagahashi Koji, Teramura Yuji, Takai Madoka
Department of Bioengineering, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Department of Bioengineering, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Colloids Surf B Biointerfaces. 2015 Oct 1;134:384-91. doi: 10.1016/j.colsurfb.2015.07.040. Epub 2015 Jul 18.
Poly(dimethylsiloxane) (PDMS)-based polymers are widely used in blood-contacting medical devices. However, the hydrophobic property causes adsorption of plasma proteins and activates blood clotting. There are several techniques for PDMS surface modification. However, the efficacy is limited to short duration due to the low glass transition temperature of PDMS. The goal of this study is to fabricate a highly stable polymer membrane with blood-compatibility on PDMS. Here, we synthesized random copolymer of 2-methacryloyloxyethyl phosphorylcholine (MPC), 3-methacryloxypropyl trimethoxysilane (MPTMSi) and 3-(methacryloyloxy) propyl-tris(trimethylsilyloxy) silane (MPTSSi). These copolymers are covalently and physically immobilized on PDMS surface by silane coupling (cross-linking) and hydrophobic interaction. Protein adsorption was significantly reduced on MPC copolymer-coated PDMS surface. In particular, copolymer containing 50% MPC unit was the most effective and maintained the effect for the longest duration (84 days). From analyses of X-ray reflectometry (XRR) and X-ray photoelectron spectroscopy (XPS), it is determined that the density of the polymer membrane is an important factor for the long-term stability. In addition, the coating of PDMS with MPC copolymer does not influence on oxygen permeability.
聚二甲基硅氧烷（PDMS）基聚合物广泛应用于与血液接触的医疗设备中。然而，其疏水性会导致血浆蛋白吸附并激活血液凝固。目前有几种PDMS表面改性技术。然而，由于PDMS的玻璃化转变温度较低，其效果仅限于短时间。本研究的目的是在PDMS上制备一种具有血液相容性的高度稳定的聚合物膜。在此，我们合成了2-甲基丙烯酰氧乙基磷酰胆碱（MPC）、3-甲基丙烯酰氧基丙基三甲氧基硅烷（MPTMSi）和3-（甲基丙烯酰氧基）丙基-三（三甲基硅氧基）硅烷（MPTSSi）的无规共聚物。这些共聚物通过硅烷偶联（交联）和疏水相互作用共价和物理固定在PDMS表面。在MPC共聚物涂层的PDMS表面，蛋白质吸附显著减少。特别是，含有50%MPC单元的共聚物最为有效，并能在最长时间（84天）内保持这种效果。通过X射线反射率（XRR）和X射线光电子能谱（XPS）分析确定，聚合物膜的密度是长期稳定性的重要因素。此外，用MPC共聚物涂覆PDMS不会影响氧气渗透性。
