Thermal Desorption
Definition
The process of heating a swab or trap to release adsorbed analyte vapour for introduction into an IMS or GC instrument. Temperature must be controlled to prevent analyte decomposition (TATP decomposes at standard GC injector temperatures; PETN partially decomposes above 220 degrees Celsius).
- Purpose
- Release adsorbed vapour from a swab or trap
- Paired detection
- IMS or GC
- Main risk
- Analyte decomposition if overheated
- Example limit
- PETN partially decomposes above 220C
Common questions
Why is TATP especially sensitive to desorption temperature?+
TATP decomposes near standard GC injector temperatures, so trace detection of it typically relies on lower-temperature interfaces such as IMS rather than conventional hot GC injection.
How is decomposition risk managed in practice?+
Instrument methods use temperature ramps and injector settings validated for the specific explosive target list, avoiding the highest injector temperatures when thermally labile compounds are expected in the sample.
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