Comparison of gas phase extraction techniques
Analysis of coffee powder using DHS, HS-SPME and Static Headspace
In order to compare different gas phase extraction techniques, 100 mg samples of a ground coffee were analyzed using static headspace, headspace-SPME and DHS. Comparable extraction conditions were chosen:
| HS | HS-SPME | DHS | |
| Temperature | 40 °C | 40 °C | 40 °C |
| Extraktion time | 30 min | 30 min | 10 min |
| Purge flow | 20 ml/min | ||
| Adsorbent | DVB/Carboxen/PDMS | Tenax |
It can be seen from the sample chromatograms and the bar graph showing relative peak areas (DHS response normalized to 100%), that DHS provided the highest response for the analytes that were determined.
For most analytes, DHS provided relative standard deviations well below 5%, which is equal to or better than the other techniques.
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