ion-pair chromatography

(IPC) -  form of liquid chromatography in which ions in solution can be "paired" or neutralized and separated as an ion pair on a reversed-phase column. Ion-pairing agents are usually ionic compounds that contain a hydrocarbon chain that imparts a certain hydrophobicity so that the ion pair can be retained on a reversed-phase column. Ion-pairing can also occur in normal-phase chromatography when one part of the pair is loaded onto a sorbent, but this technique is not as popular as the RPC technique.