Carrier Gas in Gas Chromatography

Carrier gas supply

Every chromatographic technique includes a mobile phase and a stationary phase. Mobile phase is interacted with the stationary phase in order to proceed the separation. Basically the mobile phase is gone through the mobile phase together with the test sample. Which means the test sample is carried by the mobile phase.

In gas chromatography the mobile phase is a gas. Thus in GC the mobile phase or the mobile gas is termed as the carrier gas. The carrier gas should perform several characteristics. Carrier gas should be inert, dry and free from impurities. The testing sample is either a gas or a liquid in GC. This test sample is carried onto the stationary phase by the carrier gas or the mobile gas. If carrier gas is a very reactive one, then it will perform a reaction with the test sample. If carrier gas contains moisture then of course the water molecules will react with the test sample. And also the presence of impurities will also interact with the test gas sample. Hence these features are a definite requirement of any carrier gas that is used. Usually Helium (He), Hydrogen (H2) and Nitrogen (N2) are used as carrier gases.