Microwave-Induced Plasma as an Elemental Detector for Packed-Column Supercritical Fluid Chromatography

The direct introduction of supercritical fluid chromatography effluent from a packed DeltaBond 300 phenyl column with the MIP as an elemental detector, using a high efficiency TM 010 cavity, has been employed for SFC separations. A toroidal plasma is sustained in the cavity by using an ICP type torch and an argon auxiliary flow (2 L/min) over all pressures (1500–5000 psi). Methanol modifier concentrations (0–5%) have also been studied. Studies of the effects of CO 2 on excitation temperature, electron number density, and analyte emission signals are presented. In addition, the background broad-band emission signal with 100% CO 2 and a methanol modifier up to 5% are presented.