GERSTEL Twister

Sample Extraction for GC and LC

The patented GERSTEL Twister^TM  is a magnetic stir bar that has been coated with a partitioning phase of polydimethylsiloxane (PDMS). While it is stirring the sample solution, the Twister efficiently extracts organic components from aqueous or other liquid samples or from the sample's headspace. After extracting analytes from the sample solution onto the Twister, compounds can be determined in two ways:

• For volatile compounds the Twister is placed into a GERSTEL Thermal Desorption System (TDS or TDU) where the analytes are thermally desorbed onto a GC column.
• For less volatile compounds the Twister can be solvent back extracted and injected into a liquid chromatograph.

This solventless extraction technique provides quantitative analysis with extremely low detection limits (sub parts per billion), is reproducible from bar to bar and each bar can be re-used many times.

Main Features and Advantages

• Solventless extraction
• Analyte recovery is predictable
• Quantitative analysis with low detection limits
• Reproducible
• Can be used in a wide variety of matrices
• Can be used many times

Options and Accessories

• Twister Desorption Unit - TDU
• 15 position stir plate
• 15 position storage rack
• Twister headspace vials

Applications

Downloads:

EPA Extended Abstract - Twister for EPA Methods 625 and 608

Determination of PAHs in Marine Tissue