Verification of Microphase-Separated Hypothesis of Blood Compatibility Utilizing Precisely Designed Polymer Surfaces

以正十八烷基三氯硅烷（OTS，CH_3（CH_2）_SiCl_3<17>）、18-十九烯基三氯硅烷（NTS，CH_2=CH（CH_2）_SiCl_3<17>）、[2-（全氟辛基）乙基]三氯硅烷（FOETS，CF_3（CF_2）_7CH_2CH_2SiCl_3）及其混合单分子膜为模型表面，研究了蛋白质的吸附机理。利用表面等离子体共振（SPR）技术研究了蛋白质在单分子膜表面的吸附行为。用原子力显微镜（AFM）观察了牛血清白蛋白（BSA）和γ-球蛋白（IgG）溶液对膜表面的影响。AFM观察发现，低于或高于pI的带电蛋白质优先吸附到相分离（OTS/FOETS）混合单层的FOETS相。在BSA溶液中的单层表面的原位AFM观察也揭示了BSA优先吸附到疏水的FOETS表面。SPR澄清了在荷电状态下吸附的蛋白质的量为l ...更多信息 比中立状态下的要低。当BSA吸附在混合单分子膜的FOETS相中时，带负电荷的HOOC（CH_2）_9SH化学吸附的悬臂梁针尖与OTS相之间的力-距离曲线没有检测到粘附力。这些结果表明，在低于或高于pI的混合单层系统中，蛋白质在FOETS相中的优先吸附是由于（1）单层表面和缓冲溶液之间的界面自由能最小化，（2）带电荷的蛋白质分子间的静电斥力。采用分步真空紫外光分解-化学吸附法在Si衬底上成功制备了组分微图案化的有机硅烷单层膜。通过X射线光电子能谱（XPS）证实了不同有机硅烷分子的特定区域引入。AFM和LFM观察表明，微图案化表面的线宽对应于光掩模的线宽。微图案化的官能团的表面自由能的大小的影响。蛋白质的选择性吸附，观察到这种多组分表面。少

The n-octadecyltrichlorosilane (OTS, CH_3(CH_2)_<17>SiCl_3), 18-nonadecenyltrichlorosilane (NTS, CH_2=CH(CH_2)_<17>SiCl_3), [2-(perfluorooctyl)ethyl]trichlorosilane (FOETS, CF_3(CF_2)_7CH_2CH_2SiCl_3) monolayers, and their mixed monolayers were used as model surfaces for the study of protein adsorption mechanism. Surface plasmon resonance (SPR) spectroscopy was applied to analyze the protein adsorption behavior onto the monolayer surfaces. The surfaces after exposure of these monolayers to bovine serum albumin (BSA) and γ-globulin(IgG) solutions were observed with atomic force microscope(AFM). AFM observation revealed that the charged protein either below or above pI was preferentially adsorbed onto the FOETS phase of the phase-separated (OTS/FOETS) mixed monolayer. in situ AFM observation of monolayer surfaces in BSA solution also revealed the preferential adsorption of BSA onto the hydrophobic FOETS surface. SPR clarified that the amount of adsorbed protein in the charged state was l … More ower than that in the neutral state. Adhesion force was not detected in the force-distance curve measurement between negatively-charged HOOC(CH_2)_9SH chemisorbed cantilever tip and the OTS phase in the presence of adsorbed BSA on FOETS phase of mixed monolayer. These results indicate that the preferential adsorption of protein onto the FOETS phase for the mixed monolayer systems at either below or above pI is due to (1) the minimization of interfacial free energy between the monolayer surface and the buffer solution, and (2) the electrostatic repulsion among protein molecules bearing charges.Multi-component micropatterned organosilane monolayers were successfully fabricated on Si substrate by stepwise vacuum ultraviolet-ray (VUV) photodecomposition and chemisorption process. The area-specific introduction of different organosilane molecules was confirmed by X-ray photoelectron spectroscopy (XPS). AFM and LFM observations revealed that the line-widths of micropatterned surface corresponded to those of photomask. Micropatterning of the functional groups influenced the magnitudes of surface free energy. Selective adsorption of protein was observed for this multicomponent surface. Less