A Detector for Liquid Chromatography and Flow Injection Analysis Using Surface-Enhanced Raman Spectroscopy

Abstract

A successful interface between a high-performance liquid chromatograph and a Raman spectrometer is described. Surface-enhanced techniques are utilized to overcome the sensitivity problem inherent to conventional Raman spectrometry by adding a Ag sol to the chromatographic effluent in a post-column mixing coil. The system is designed so that Raman spectra may be obtained from chromatographic effluent or from flow injection analysis effluent. A common organic dye (pararosaniline hydrochloride) is used to evaluate the reproducibility, dynamic range, and analytical capabilities of the system. The SERS instrument is found to be a viable detector for HPLC and FIA, capable of providing structural information with a sensitivity comparable to that of other commonly used HPLC detectors.