ITEX Sampling on the TriPlus RSH SMART
Topic
In-Tube Extraction (ITEX) is a syringe-based headspace enrichment technique that uses a gas-tight syringe and a sorbent-filled micro-trap inside the syringe needle to trap and concentrate volatile compounds.
Environment
- TriPlus RSH SMART autosampler
- GC or GC-MS
- ITEX syringe
- Gas-tight syringe
- Sorbent-filled micro-trap
- Incubator
- Nitrogen supply for trap cleaning
Steps/Procedure
- Place the sample in the incubator.
- Pre-equilibrate the sample at the selected constant temperature and agitation speed.
- Collect volatile compounds from the vial headspace using the ITEX syringe.
- Perform repeated syringe strokes through the headspace as defined by the method.
- Allow volatile analytes to become trapped and concentrated on the sorbent in the micro-trap.
- Insert the ITEX needle into the GC injector.
- Thermally desorb the trapped analytes through the GC inlet and into the analytical column.
- After analysis, heat the ITEX syringe and needle.
- Purge the syringe and needle with nitrogen to clean the trap.
Additional Information
The training identifies the following benefits of ITEX:
- High sorbent capacity
- Increased sensitivity at lower detection limits
- Robustness
- Ease of use
- Long trap lifetime
The training references an ITEX-DHS GC-MS application for trace-level odorants in water, including isoborneol, 2-methyl-isoborneol, 2,4,6-trichloroanisole, and geosmin.
Source terminology note: The training materials are not completely consistent in how ITEX is categorized. One slide describes ITEX as a “syringe-based static headspace enrichment technique,” while the summary describes it as a “dynamic headspace enrichment technique.” This article therefore uses the broader source-supported description “syringe-based headspace enrichment technique” rather than resolving the discrepancy without additional technical documentation.