Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan 70101.
Langmuir. 2011 Jun 7;27(11):7091-8. doi: 10.1021/la200906b. Epub 2011 May 12.
In this study, the mixed self-assembled monolayers (SAMs) containing the mixture of long-chain alkanethiol, SH(CH(2))(11)NH(2) and SH(CH(2))(10)SO(3)H, was prepared as a model surface to examine the interaction between the biological environment and artificial surface. The 10% (v/v) NH(4)OH ethanolic solution and DMSO were chosen as the solvents for the preparation of these mixed SAMs and the "solvent effect" was discussed. X-ray photoelectron spectroscopy (XPS) has indicated that -SO(3)H/-NH(2) mixed SAMs formed from 10% (v/v) NH(4)OH ethanolic solution were surface "-SO(3)H poor", while a nearly equivalent amount of surface -SO(3)H functionality was presented on the mixed SAMs formed from DMSO. This has resulted from the different solvation capability between solvent molecules and the alkanethiol. Such solvent effects were also reflected in various surface properties such as surface wettability and surface zeta potential. The mixed SAMs formed from DMSO were more surface hydrophilic and less negatively surface charged than from 10% (v/v) NH(4)OH ethanolic solution. In addition, these mixed SAMs formed from DMSO exhibited the least amount of protein adsorbed as well as a better platelet compatibility than its counterpart from 10% (v/v) NH(4)OH ethanolic solution. These findings indicated that choosing a proper solvent for mixed zwitterionic SAM can greatly affect its surface properties and biocompatibility, such as to form a surface with near neutrality for reducing protein adsorption and subsequent platelet adhesion and activation.
在这项研究中，制备了含有长链烷硫醇 SH(CH(2))(11)NH(2)和 SH(CH(2))(10)SO(3)H 的混合物的混合自组装单层（SAM）作为模型表面，以研究生物环境与人工表面之间的相互作用。选择 10%（v/v）氨乙醇溶液和 DMSO 作为制备这些混合 SAM 的溶剂，并讨论了“溶剂效应”。X 射线光电子能谱（XPS）表明，由 10%（v/v）氨乙醇溶液形成的-SO(3)H/-NH(2)混合 SAM 表面“-SO(3)H 贫乏”，而由 DMSO 形成的混合 SAM 表面呈现出几乎等量的-SO(3)H 官能团。这是由于溶剂分子和烷硫醇之间的不同溶剂化能力所致。这种溶剂效应也反映在各种表面性质上，如表面润湿性和表面zeta 电位。由 DMSO 形成的混合 SAM 比由 10%（v/v）氨乙醇溶液形成的混合 SAM 具有更高的表面亲水性和更低的表面负电荷。此外，与由 10%（v/v）氨乙醇溶液形成的混合 SAM 相比，由 DMSO 形成的混合 SAM 吸附的蛋白质量最少，血小板相容性最好。这些发现表明，选择合适的溶剂制备混合两性离子 SAM 可以极大地影响其表面性质和生物相容性，例如形成表面接近中性以减少蛋白质吸附以及随后的血小板黏附和激活。
