The DHS option efficiently extracts and concentrates VOCs from liquid or solid samples placed in standard 10 mL or 20 mL headspace vials (DHS) or in larger sample containers (250 mL, 500 mL or 1 L) using the the DHSLarge extension. The sample is thermostated and agitated while the headspace is purged with a controlled flow of inert gas, providing controlled and efficient extraction conditions. Sample temperatures can be selected from 10 °C to 200 °C. Lowering the temperature provides a means of reducing the amount of water vapor released and ultimately re-trapped. The DHS option provides an independent rack of adsorbent tubes that are used for analyte trapping/concentration. Unlike all other purge-and-trap or dynamic headspace type systems, the GERSTEL DHS can automatically select which trap to use for each sample if desired. The temperature of the adsorbent tube during the DHS process can be varied from 20 °C to 70 °C for optimal trapping of the analytes of interest.
TDU or TD 3.5+ tubes can be used depending on which DHS option is installed. Following analyte trapping/concentration, the tube is automatically transferred to the TDU/TD 3.5+ for thermal desorption and analyte transfer to the GC. Tubes are fitted with individual adapters enabling both automated movement and leak-free sealing during the dynamic headspace and thermal desorption steps and during storage in the autosampler tray.
The DHS option is completely controlled by GERSTEL MAESTRO software which provides simple method and sequence set-up and parallel processing for over 100 samples. can be run in one sequence using different method parameters
Main Features and Advantages
- The GERSTEL Dynamic Headspace option provides lower detection limits than static headspace, SPME and other widely used techniques
- Becoming sampling technique of choice due to little or no analyte discrimination during sampling process
- High productivity through high throughput design and complete automation from sample preparation to GC/MS-analysis
- Highest flexibility: User defined extraction time, flow, temperature and adsorbent
- The Dynamic Headspace technology provides multiple water management options to ensure best chromatography and MS stability
- Allows user selected packed TDU/TD 3.5+ tubes to be used for analyte trapping/concentration
- Excellent reproducibility through precise temperature and flow control.
- Extremely low detection limits.