An alternative GC-ICP-MS interface design for trace element speciation

The design, construction and performance characteristics of an easily remov able interface to couple a gas chromatograph (GC) to an inductively coupled plasma mass spectrometer (ICP-MS) for trace element speciation is describe d. The interface is based on the use of a heated metallic tube where the la st part of the capillary GC column is inserted. This metallic tube is conne cted to a metallic T-piece where a flow of argon carrier gas is introduced perpendicularly and externally to the metallic tube, creating a high veloci ty flow of intermediate sheath gas, which prevents condensation of the anal ytes eluting from the column on the walls of the T-piece or on the connecti on tubing to the ICP-MS torch. A flexible non-heated PTFE tube is used to c onnect the exit of the T-piece to the ICP-MS torch. This new interface has been applied to the separation and detection of different organometallic co mpounds of Se, S, Pb, Hg and Sn.