Abstract: A three-electrode surface-enhanced Raman spectroscopy detector, with a Ag working electrode, Pt foil auxiliary electrode and SCE reference and a cell volume of 30 µL, was evaluated for use with HPLC and flow injection analysis. In a flowing system, the analyte is rapidly removed from the electrode surface in 10 s, and spectra was obtained in 5 s with an optical multichannel analyzer.. Under stopped-flow conditions, detection limits were 175, 233 and 211 pmol for adenine, thymine and cytosine, respectively.

Abstract: A Ag-ring reference (diameter 5 mm) and a Ag-disc working electrode (diameter 3 mm) were sealed 1 mm apart in a Pyrex tube (o.d. 7 mm) and polished smooth. The Ag ring was anodized at 0.4 V (vs. a SCE) in 0.1 M KCl to produce a Ag - AgCl reference electrode with a potential of ~0.190 to ~0.200 V (vs. a NHE) in the 0.1 M KCl used as mobile phase and supporting electrolyte. The apparatus was applied in flow injection analysis for 50.0 mM pyridine (1 mL injections) in KCl flowing at 2 mL min-1. The potential was held at -0.6 V. Raman spectra were recorded from 990 to 1050 cm-1 in 2-cm-1 steps. A detection limit of ~250 nM was achieved. A Ag-ring reference (diameter 5 mm) and a Ag-disc working electrode (diameter 3 mm) were sealed 1 mm apart in a Pyrex tube (o.d. 7 mm) and polished smooth.