Kearns H, Shand N C, Smith W E, Faulds K, Graham D
Centre for Molecular Nanometrology, West CHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral St., Glasgow, G1 1XL, UK.
Phys Chem Chem Phys. 2015 Jan 21;17(3):1980-6. doi: 10.1039/c4cp04281f. Epub 2014 Dec 5.
Surface enhanced Raman scattering (SERS) tags are in situ probes that can provide sensitive and selective probes for optical analysis in biological materials. Engineering tags for use in the near infrared (NIR) region is of particular interest since there is an uncongested spectral window for optical analysis due to the low background absorption and scattering from many molecules. An improved synthesis has resulted in the formation of hollow gold nanoshells (HGNs) with a localised surface plasmon resonance (LSPR) between 800 and 900 nm which provide effective SERS when excited at 1064 nm. Seven Raman reporters containing aromatic amine or thiol attachment groups were investigated. All were effective but 1,2-bis(4-pyridyl)ethylene (BPE) and 4,4-azopyridine (AZPY) provided the largest enhancement. At approximately monolayer coverage, these two reporters appear to pack with the main axis of the molecule perpendicular or nearly perpendicular to the surface giving strong SERS and thus providing effective 1064 nm gold SERS nanotags.
表面增强拉曼散射（SERS）标签是原位探针，可为生物材料中的光学分析提供灵敏且具选择性的探针。用于近红外（NIR）区域的工程化标签尤其受关注，因为由于许多分子的背景吸收和散射较低，存在用于光学分析的未拥挤光谱窗口。一种改进的合成方法已导致形成空心金纳米壳（HGN），其局部表面等离子体共振（LSPR）在800至900nm之间，当在1064nm激发时可提供有效的SERS。研究了七种含有芳胺或硫醇连接基团的拉曼报告分子。所有这些都有效，但1,2-双（4-吡啶基）乙烯（BPE）和4,4'-偶氮吡啶（AZPY）提供了最大的增强效果。在大约单层覆盖时，这两种报告分子似乎以分子的主轴垂直或几乎垂直于表面的方式堆积，从而产生强烈的SERS，因此提供了有效的1064nm金SERS纳米标签。
