Raman spectroscopy as a detection method for liquid-separation techniques

Raman spectroscopy has considerable identification power but is, nevertheless, seldom used for detection in liquid-separation methods such as column liquid chromatography and capillary electrophoresis. This is mainly due to its poor analyte detectability. This review gives attention to the improved performance effected by instrumental developments (e.g., laser technology and liquid-core waveguide detector cells) and the proper use of analyte-enrichment techniques. However, the main emphasis is on the benefits that derive from using special Raman modes, such as resonance Raman and surface-enhanced (resonance) Raman spectroscopy. The most promising on-line and at-line set-ups are highlighted, and the detectability vs. identification dilemma is explained. To achieve a real breakthrough, relevant real-life applications will be crucial.