Detection methods in superheated water chromatography

Because water at elevated temperatures can be used as a mobile phase for reversed-phase HPLC or as an extraction solvent, it has attracted considerable recent interest as a green mobile phase, avoiding the use of organic solvents in analytical chemistry. Because of the low vapour pressure of water, even at 200 °C, the instrumentation required is simple and standard HPLC systems can be readily adapted by the addition of a high temperature oven and the creation of a pressure restrictor. This can be as simple as a 2-3 m length of narrow bore PEEK tubing or a mechanical SFC type restrictor .