GAS GC-IMS, User Manual

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GC-IMS
– User Manual
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Figure 3: IMS Predominant Ionization (positive polarization)
The above figure exemplarily shows typical IMS spectra without analyte and with
analyte. The RIP is formed as a sharp signal proving the cleanliness of the system
and at a specific position that is used as internal standard. The spectrum containing
analytes shows a decreased RIP, while new (analyte) peaks are correspondingly
formed. The drift time is specific of an ion, therefore analyte identification is possible.
The peak height and area correlate to the analyte concentration, so that a
quantification is also possible.
Figure 4: Protone Affinities of VOC's