Enhanced sensitivity and selectivity of a gas chromatography microwave-induced plasma atomic emission system (GC-MIP) at the 685.6-nm fluorine emission line

As part of the studies for the characterization of a gas chromatography wit h microwave-induced plasma atomic emission detection (GC-MIP) prototype, it s behavior at the 685.6-nm fluorine emission line was studied with isooctan e solutions of n-perfluoroheptane and benzene. This test mixture was chroma tographed under varied conditions of the plasma support helium flow rate an d microwave input power. A relatively high value of (3.9 +/- 0.3) x 10(4) w as found for the fluorine to carbon selectivity, with detection limits for fluorine as low as 1.3 +/- 0.2 pg(F).s(-1). These levels for the selectivit y and for the detection limit compare favorably with previous reports found in the literature for other GC-MIP systems. (C) 1999 John Wiley & Sons, In c.