Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, United Kingdom.
J Am Chem Soc. 2011 Mar 2;133(8):2749-59. doi: 10.1021/ja1103662. Epub 2011 Feb 8.
An approach to the integration of nanolithography with synthetic chemical methodology is described, in which near-field optical techniques are used to selectively deprotect films formed by the adsorption of aminosilanes protected by modified 2-nitrophenylethoxycarbonyl (NPEOC) groups. The NPEOC groups are functionalized at the m- or p-position with either a tetraethyleneglycol or a heptaethylene glycol adduct. We describe the synthesis of these bioresistant aminosilanes and the characterization of the resulting photoreactive films. Photodeprotection by exposure to UV light (λ = 325 nm) yielded the amine with high efficiency, at a similar rate for all four adsorbates, and was complete after an exposure of 2.24 J cm(-2). Following photodeprotection, derivatization by trifluoroacetic anhydride was carried out with high efficiency. Micropatterned samples, formed using a mask, were derivatized with aldehyde-functionalized polymer nanoparticles and, following derivatization with biotin, were used to form patterns of avidin-coated polymer particles. Fluorescence microscopy and atomic force microscopy data demonstrated that the intact protecting groups conferred excellent resistance to nonspecific adsorption. Nanometer-scale patterns were created using scanning near-field photolithography and were derivatized with biotin. Subsequent conjugation with avidin-functionalized polymer nanoparticles yielded clear fluorescence images that indicated dense attachment to the nanostructures and excellent protein resistance on the surrounding surface. These simple photocleavable protecting group strategies, combined with the use of near-field exposure, offer excellent prospects for the control of surface reactivity at nanometer resolution in biological systems and offer promise for integrating the top-down and bottom-up molecular fabrication paradigms.
描述了一种将纳米光刻技术与合成化学方法相结合的方法，其中采用近场光学技术选择性地去除由经修饰的 2-硝基苯氧基羰基（NPEOC）基团保护的氨硅烷吸附形成的薄膜。NPEOC 基团在 m-或 p-位上与四乙二醇或七乙二醇加合物功能化。我们描述了这些生物抗性氨硅烷的合成以及所得光反应性薄膜的表征。光解保护通过暴露于紫外光（λ=325nm）以高效率进行，对于所有四种吸附剂，其速率相似，并且在 2.24Jcm（-2）的暴露后完全进行。光解保护后，用三氟乙酸酐进行高效衍生化。使用掩模形成的微图案样品用醛官能化聚合物纳米粒子进行衍生化，并且在衍生化用生物素后，用于形成经抗生物素蛋白包被的聚合物颗粒的图案。荧光显微镜和原子力显微镜数据表明，完整的保护基团赋予了优异的抗非特异性吸附能力。使用扫描近场光刻术创建纳米级图案，并进行生物素衍生化。随后与具有抗生物素蛋白功能的聚合物纳米粒子缀合，得到清晰的荧光图像，表明在纳米结构上的密集附着以及周围表面上的优异蛋白质抗性。这些简单的光可裂解保护基团策略，结合近场暴露的使用，为在生物系统中以纳米分辨率控制表面反应提供了极好的前景，并为整合自上而下和自下而上的分子制造范例提供了希望。
