Flow-injection analysis and liquid chromatography: surface-enhanced Raman spectrometry detection by using a windowless flow cell

A windowless flow cell for detection by surface-enhanced Raman spectrometry (SERS) in two flow systems, flow-injection analysis and liquid chromatography (LC), has been developed. Several experimental parameters including flow-rates of silver colloid suspension and mobile phase, photon-counting integration time and bandpass of the spectrometer have been examined. The effects of those parameters on the SERS intensities, and the limit of detection values, of five drugs (amiloride, amiphenazole, 2-mercaptopyridine, pemoline and triamterene) under flowing conditions were evaluated. The maximum SERS signal was found for flow-rates of 0.075 ml min−1 and 1.5 ml min−1 for the mobile phase and silver hydrosol, respectively.