Department of Chemistry, University of Western Ontario, London, Ontario, Canada.
Langmuir. 2011 Feb 15;27(4):1494-8. doi: 10.1021/la1047497. Epub 2011 Jan 18.
A two-dimensional array of gold nanotriangles inscribed onto glass coverslips were optimized for the surface-enhanced Raman detection of streptavidin/biotin monolayer assemblies. The nanostructures were fabricated by electron beam lithography, and its optical parameters were optimized to be probed under a Raman microscope with a linearly polarized He-Ne laser with an excitation wavelength of λ = 632.8 nm. The platforms were first tested against a monolayer of biotinylated alkanethiols (BAT) functionalized over the gold nanostructure, showing that good-quality spectra could be acquired with a short acquisition time. The supramolecular interaction of streptavidin (strep) with BAT showed subsequent modification of the Raman spectrum that implies a change in the secondary structure of the host biomolecule (streptavidin). Compared to gold surfaces without nanoscale structures, the local enhancement that results from our nanostructured surfaces allows one to detect the vibrational signal of monolayers within a time on the order of seconds and under modest laser intensity, further demonstrating the utility of using plasmonic metallic nanostructures for molecular recognition.
在玻璃盖玻片上刻蚀的二维金纳米三角形阵列经过优化，可用于表面增强拉曼检测链霉亲和素/生物素单层组装。该纳米结构通过电子束光刻技术制造，并对其光学参数进行优化，以便在具有激发波长为 λ = 632.8nm 的线性偏振氦氖激光的拉曼显微镜下进行探测。该平台首先用功能化于金纳米结构上的生物素化烷硫醇 (BAT) 的单层进行了测试，结果表明可以用短的采集时间获得高质量的光谱。链霉亲和素 (strep) 与 BAT 的超分子相互作用表明，拉曼光谱随后发生了修饰，这意味着主体生物分子（链霉亲和素）的二级结构发生了变化。与没有纳米级结构的金表面相比，我们的纳米结构表面产生的局部增强使得能够在几秒钟的时间内检测到单层的振动信号，并且在适度的激光强度下，进一步证明了使用等离子体金属纳米结构进行分子识别的实用性。
