GAS BreathSpec, Руководство пользователя

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BreathSpec®
– User Manual
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Complex analyte mixtures, like e.g. food flavours, often demand a second and
independent separation step to separately analyse the multiplicity of compounds at
low concentrations. Therefore G.A.S. -according to application- equips 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 are consecutively fed into the IMS ionization chamber, so that analyte
and/or ion interactions are avoided.
Furthermore, a competition of analytes on the reactant ions is excluded, enhancing
the sensitivity of the system for individual compounds.
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.
Figure 5: GC-IMS measurement 3D
The above figure sketches the GC-
IMS measurement‘s 3D-dataset and the
corresponding heatmap visualization.