Optoelectronics and Measurement Techniques Research Unit, Faculty of Information Technology and Electrical Engineering, University of Oulu, Oulu 90570, Finland and Institute of Analytical and Bioanalytical Chemistry, Ulm University, 89081 Ulm, Germany.
Institute of Analytical and Bioanalytical Chemistry, Ulm University, 89081 Ulm, Germany.
Analyst. 2017 Mar 13;142(6):951-958. doi: 10.1039/c6an02596j.
We report the preparation and characterization of plasmonic chip-based systems comprising self-assembled gold nanostars at silicon substrates that enable concomitantly enhanced Raman (surface enhanced Raman spectroscopy; SERS) and mid-infrared (surface enhanced infrared reflection or absorption spectroscopy; SEIRA) spectral signatures. The high-aspect-ratio structure of gold nanostars provides an increased number of hot spots at their surface, which results in an electric field enhancement around the nanomaterial. Gold nanostars were immobilized at a silicon substrate via a thin gold layer, and α-ω-dimercapto polyethylene glycol (SH-PEG-SH) linkers. The Raman and IR spectra of crystal violet (CV) revealed a noticeable enhancement of the analyte vibrational signal intensity in SERS and SEIRA studies resulting from the presence of the nanostars. Enhancement factors of 2.5 × 10 and 2.3 × 10 were calculated in SERS considering the CV bands at 1374.9 cm and 1181 cm, respectively; for SEIRA, an enhancement factor of 5.36 was achieved considering the CV band at 1585 cm.
我们报告了等离子体芯片基系统的制备和表征，该系统由硅衬底上自组装的金纳米星组成，能够同时增强拉曼（表面增强拉曼光谱；SERS）和中红外（表面增强红外反射或吸收光谱；SEIRA）光谱特征。金纳米星的高纵横比结构在其表面提供了更多的热点，从而导致纳米材料周围的电场增强。金纳米星通过薄金层和α-ω-二巯基聚乙二醇（SH-PEG-SH）接头固定在硅衬底上。结晶紫（CV）的拉曼和红外光谱显示，由于纳米星的存在，SERS 和 SEIRA 研究中分析物振动信号强度的显著增强。在 SERS 中，考虑到 1374.9 cm 和 1181 cm 处的 CV 带，计算出 2.5×10 和 2.3×10 的增强因子；对于 SEIRA，考虑到 1585 cm 处的 CV 带，实现了 5.36 的增强因子。
