Zangmeister Rebecca A, Maslar James E, Opdahl Aric, Tarlov Michael J
National Institute of Standards and Technology, 100 Bureau Drive, MS 8362, Gaithersburg, Maryland 20899-8362, USA.
Langmuir. 2007 May 22;23(11):6252-6. doi: 10.1021/la063109e. Epub 2007 Apr 25.
We have examined the adsorption of DNA-wrapped single-walled carbon nanotubes (DNA-SWNTs) on hydrophobic, hydrophilic, and charged surfaces of alkylthiol self-assembled monolayers (SAMs) on gold. Our goal is to understand how DNA-SWNTs interact with surfaces of varying chemical functionality. These samples were characterized using reflection absorption FTIR (RAIRS), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. We have found that DNA-SWNTs preferentially adsorb to positively charged amine-terminated SAMs and to bare gold surfaces versus hydrophobic methyl-terminated or negatively charged carboxylic acid-terminated SAMs. Examination of the adsorption on gold of single-strand DNA (ssDNA) of the same sequence used to wrap the SWNTs suggests that the DNA wrapping plays a role in the adsorption behavior of DNA-SWNTs.
我们研究了包裹有DNA的单壁碳纳米管（DNA-SWNTs）在金表面的烷基硫醇自组装单分子层（SAMs）的疏水、亲水和带电表面上的吸附情况。我们的目标是了解DNA-SWNTs如何与具有不同化学功能的表面相互作用。这些样品通过反射吸收傅里叶变换红外光谱（RAIRS）、X射线光电子能谱（XPS）和拉曼光谱进行表征。我们发现，与疏水的甲基封端或带负电荷的羧酸封端的SAMs相比，DNA-SWNTs优先吸附到带正电荷的胺封端的SAMs和裸露的金表面上。对用于包裹SWNTs的相同序列的单链DNA（ssDNA）在金表面的吸附研究表明，DNA包裹在DNA-SWNTs的吸附行为中起作用。
