Simultaneous element-selective detection of C, F, Cl, Br, and I by capillary gas chromatography coupled with microplasma mass spectrometry

Simultaneous element-selective detection of the halogens and carbon was acc omplished with capillary gas chromatography coupled with microplasma mass s pectrometry, The microplasma ion source was a radio frequency plasma contai ned inside the last 4-5 cm of the 0.32 mm i.d. fused silica capillary colum n, The ion source was located inside the high vacuum housing of the MS, and only the GC carrier gas (2.3 mL min(-1) of helium) was used for plasma gen eration. Atomic ions were detected in the positive mode, Detection limits w ere in the tow picogram area, and the selectivity to carbon ranged from 8x1 0(2) for fluorine to higher than 10(4) for the other halogens, By introduct ion of both hydrogen and oxygen as reagent gases, peak tailing was avoided by suppression of analyte reactions with the silica walls of the ion source . Special attention was given to the fluorine-selective detection due to an interfering background species at m/z 19, assumed to be H3O+ originating f rom the reagent gases, The background signal was minimized by careful contr ol of the power level.