APPLICATION OF SELECTIVITY TUNING IN SERIES-COUPLED CAPILLARY GC COLUMNS FOR THE EXACT QUANTIFICATION OF THE QUENCHING EFFECT IN FPD DETECTION

In a series-coupled system of two capillary columns with different polarity, a controlled overlapping of sulphur-containing and sulphur-free compounds can be achieved by means of different mid-point pressure settings. By means of this selectivity tuning it is possible to measure exactly the quenching of the flame photometric detector signal for a sulphur compound coeluted with an excess of a sulphur-free compound. With the example of a complex sample it is shown that, with a suitable system of columns, selectivity tuning can give quench-free FPD chromatograms or chromatograms with quench-free regions. © 1990 Friedr. Vieweg & Sohn Verlagsgesellschaft mbH.