Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Wisconsin 53706, United States.
ACS Nano. 2011 Oct 25;5(10):7899-909. doi: 10.1021/nn2021277. Epub 2011 Sep 14.
DNA oligonucleotides of different sequences were patterned at the nanoscale. Areas of positive charge were generated by exposure of insulating substrates, spin-on hydrogen silsesquioxane or vapor-deposited SiO(2) on Si, with ionizing radiation sources used in electron beam and extreme ultraviolet lithography. Au nanoparticles (NPs) with a diameter of 15 nm, carrying covalently bound negatively charged single-stranded DNA oligonucleotides, were site specifically immobilized directly on the exposed regions and presented oligonucleotides for subsequent hybridization. Repeated exposure and deposition of NPs allowed for patterning multiple DNA sequences. Patterns with dimensions as small as 15 nm were fabricated using electron beam lithography. The use of DNA-functionalized NPs rather than just DNA facilitates metrology in scanning electron microscopy and improves the hybridization efficiency of the oligonucleotides on the surface.
不同序列的 DNA 寡核苷酸被纳米级图案化。正电荷区域是通过暴露于绝缘衬底、旋涂氢倍半硅氧烷或气相沉积的二氧化硅（SiO 2 ）在硅上来产生的，使用电子束和极紫外光刻中的电离辐射源。直径为 15nm 的金纳米颗粒（NPs）带有共价结合的带负电荷的单链 DNA 寡核苷酸，直接固定在暴露的区域上，并呈现出随后进行杂交的寡核苷酸。重复的 NPs 暴露和沉积允许对多个 DNA 序列进行图案化。使用电子束光刻可以制造出尺寸小至 15nm 的图案。使用 DNA 功能化的 NPs 而不仅仅是 DNA 有助于在扫描电子显微镜中进行计量，并提高表面上寡核苷酸的杂交效率。
