Department of Chemistry, ‡Department of Physics and Astronomy, §Department of Electrical and Computer Engineering, and ∥Laboratory for Nanophotonics and the Smalley-Curl Institute, Rice University , 6100 Main Street, Houston, Texas 77005, United States.
Nano Lett. 2017 Aug 9;17(8):5071-5077. doi: 10.1021/acs.nanolett.7b02338. Epub 2017 Jul 6.
Since its discovery in the 1970s, surface-enhanced Raman scattering (SERS) has been primarily associated with substrates composed of nanostructured noble metals. Here we investigate chemically synthesized nanocrystal aggregates of aluminum, an inexpensive, highly abundant, and sustainable metal, as SERS substrates. Al nanocrystal aggregates are capable of substantial near-infrared SERS enhancements, similar to Au nanoparticles. The intrinsic nanoscale surface oxide of Al nanocrystals supports molecule-substrate interactions that differ dramatically from noble metal substrates. The preferential affinity of the single-stranded DNA (ssDNA) phosphate backbone for the Al oxide surface preserves both the spectral features and nucleic acid cross sections relative to conventional Raman spectroscopy, enabling quantitative ssDNA detection and analysis.
自 20 世纪 70 年代发现以来，表面增强拉曼散射（SERS）主要与由纳米结构贵金属组成的基底相关联。在这里，我们研究了化学合成的纳米晶体聚集体作为 SERS 基底的铝，一种廉价、丰富且可持续的金属。铝纳米晶体聚集体能够实现大量的近红外 SERS 增强，类似于金纳米颗粒。铝纳米晶体的固有纳米级表面氧化物支持分子-基底相互作用，与贵金属基底有很大的不同。单链 DNA（ssDNA）磷酸骨架对铝氧化物表面的优先亲和力保留了相对于传统拉曼光谱的光谱特征和核酸截面，从而能够进行定量的 ssDNA 检测和分析。
