Photocatalytic nanolithography of self-assembled monolayers and proteins.
Photocatalytic nanolithography of self-assembled monolayers and proteins.
复制标题
自组装单层和蛋白质的光催化纳米光刻。
作者：
Ul-Haq E
自组装单分子膜的烷基硫醇盐的金和烷基硅烷的二氧化硅上已被图案化的光催化亚100 nm的长度尺度上使用有孔近场和apertureless方法。通过耦合到具有沉积在孔径上的二氧化钛薄膜的双折射型近场探针的氩离子激光器（364 nm）进行光刻。用氦-镉激光器（325 nm）激发涂钛的接触式原子力显微镜（AFM）探针进行无源光刻。后一种方法很容易在任何商业AFM系统上实现。光降解发生在这两种情况下，通过局部的单分子层的光催化降解。对于烷硫醇，一种硫醇的降解暴露了裸露的基底，使得裸露的金能够被第二种对比硫醇重新官能化。对于烷基硅烷，吸附物分子的降解提供了一个简单的手段，蛋白质图案。线写在由低聚（乙二醇）官能化的三氯硅烷在玻璃上的吸附形成的抗蛋白质的膜，导致形成的子100 nm的粘合剂，去功能化的区域。这些衍生与aminobutylnitrilotriacetic酸，并与Ni 2+络合，使组氨酸标记的绿色荧光蛋白，产生明亮的荧光从70 nm宽的线，可以清楚地在共聚焦显微镜成像的结合。
Self-assembled monolayers of alkylthiolates on gold and alkylsilanes on silicon dioxide have been patterned photocatalytically on sub-100 nm length-scales using both apertured near-field and apertureless methods. Apertured lithography was carried out by means of an argon ion laser (364 nm) coupled to cantilever-type near-field probes with a thin film of titania deposited over the aperture. Apertureless lithography was carried out with a helium–cadmium laser (325 nm) to excite titanium-coated, contact-mode atomic force microscope (AFM) probes. This latter approach is readily implementable on any commercial AFM system. Photodegradation occurred in both cases through the localized photocatalytic degradation of the monolayer. For alkanethiols, degradation of one thiol exposed the bare substrate, enabling refunctionalization of the bare gold by a second, contrasting thiol. For alkylsilanes, degradation of the adsorbate molecule provided a facile means for protein patterning. Lines were written in a protein-resistant film formed by the adsorption of oligo(ethylene glycol)-functionalized trichlorosilanes on glass, leading to the formation of sub-100 nm adhesive, aldehyde-functionalized regions. These were derivatized with aminobutylnitrilotriacetic acid, and complexed with Ni2+, enabling the binding of histidine-labeled green fluorescent protein, which yielded bright fluorescence from 70-nm-wide lines that could be imaged clearly in a confocal microscope.