Supported Liquid Extraction: The Best-Kept Secret in Sample Preparation

Supported liquid extraction (SLE) has been around for a long time, but surprisingly it is seldom used to replace classical liquid-liquid extraction (LLE). In SLE, the same organic phases used in LLE are coated onto an inert diatomaceous earth, but instead of shaking two immiscible phases together, the aqueous phase is passed through the column (or cartridge) and a very efficient extraction takes place. SLE offers many advantages over LLE, including equivalent or more efficient extraction, no emulsion formation, easy automation, less organic solvent use, less labour and less glassware.