Topics - Carrier gas
The term carrier gas
was introduced by A. J. P .Martin, the inventor of gas chromatography who used it as an alternative term for the mobile phase; obviously, the term could only be used as such in gas chromatography. The term has persisted and is still used synonymously for a gaseous mobile phase. The carrier gas can be any inert gas (a gas that can not react with either the solutes or the stationary phase) such as helium, argon, nitrogen, and under certain circumstances hydrogen. The gas that is used is sometimes dictated by the detector, e.g., the argon detector requires argon to be used as the carrier gas. With no other restrictions, helium is the most popular carrier gas used in gas chromatography although it is the most expensive. Helium has a low density and solutes have a high diffusivity in it. Thus, high gas velocities can be used providing faster analyses without seriously denigrating the performance of the column.