Abstract
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 × 103 and 2.3 × 103 were calculated in SERS considering the CV bands at 1374.9 cm-1 and 1181 cm-1, respectively; for SEIRA, an enhancement factor of 5.36 was achieved considering the CV band at 1585 cm-1.
Original language | English |
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Pages (from-to) | 951-958 |
Journal | Analyst |
Volume | 142 |
Issue number | 6 |
DOIs | |
Publication status | Published - 21 Mar 2017 |
MoE publication type | A1 Journal article-refereed |