Octopole Reaction System (ORS)

The ORS is a a type of collision/reaction cell used in inductively coupled plasma mass spectrometry to remove interfering ions through ion/neutral reactions. As the name implies, the cell is using a octople instead of a quadruple. The octopole reaction system (ORS)) uses only helium or hydrogen and the volume of the cell is smaller than that of a DRC. The small molecules of helium and hydrogen collide with the large, unwanted polyatomic ions formed in the plasma and break them up into other ions that can be separated in the quadrupole mass analyser. However, unlike the DRC the OCR system is based only on collision reactions and not on chemical reactions.