MOLECULAR-SPECIFIC CHROMATOGRAPHIC DETECTOR USING MODIFIED SERS SUBSTRATES

摘要

Preliminary results for a gas chromatography detector based on surface enhanced Raman scattering (SERS) spectroscopy are described, The method described uses a SERS substrate that has been modified with a propanethiol coating that creates a hydrophobic interface to promote adsorption, The coating also prevents oxidation of the silver surface and stabilizes the SERS effect. The detector was tested with a separation of benzene, toluene, ethylbenzene, and o,m,p-xylenes using a capillary column. The results demonstrate that a SERS detector is able to spectrally separate the chromatographically unresolved and detect a mixture component, benzene, at the 40 ng mass detection level, The temperature dependence of the GC-SERS cell was examined, and it was shown how reversibility of the detector is related to temperature, [References: 12]