On-line coupled superheated water extraction (SWE) and superheated water chromatography (SWC)

Superheated water extraction has been linked directly to a superheated water chromatographic separation so that the process of sample extraction and separation can be achieved without the need for organic solvents at any stage. A model matrix spiked with pharmaceuticals and antioxidants was extracted and the extracted components were collected on a cold polystyrene-divinylbenzene trap. The analytes were then sequentially released by raising the temperature in stages. Each fraction was passed on-line to a polystyrene divinylbenzene analytical column and was eluted with superheated water using a thermal gradient.