To overcome the limitation of IMS with regard to separation efficiency G.A.S. equips almost all of its IMS systems with gas chromatographic (GC) columns. The
volatile compounds of samples under testing are pre-separated in time
by a GC column. The discrete compounds elute directly into the IMS ionization chamber, so that analyte and/or ion interactions and a competition of analytes on the
reactand ions can be
avoided. This set-up enhances the sensitivity of the detector towards individual
The GC-IMS setup enables a twofold separation of analyte mixtures and the detection by the IMS electrometer. Since the IMS measurements are extremely fast (30ms / spectrum) a continuous and high-resolution recording of analyte signals is provided. Shown figure sketches the GC-IMS sample flow and detection leading to a 3D-dataset of GC- and IMS separation, same as the corresponding intensity which are processed using G.A.S. VOCal and additional software tools.