EPED GC-Detektor
Trace analysis of halogen and sulfur compounds
The GC detector EPED (Echelle Plasma Emission Detector) is an element-specific detector for the elements fluorine, chlorine, bromine, iodine and sulfur. Compared to the also element-specific AED (atomic emission detector), the detection limits are lower by a factor of 5 - 10. The low-maintenance detector shows a good reproducibility and at the same time good linearity over a wide concentration range (3 - 4 decades). An advantage is the equimolar response of the Echelle spectrometer, making quantitation of unknowns and samples without standards possible.
EPED Principle
The operating principle of the detector is based on the atomization of molecules introduced into a helium plasma. The detector is mounted on the gas chromatograph so that the analytes from the GC column enter the plasma cell directly. The emitted light is guided via an optical fiber into the high-resolution Echelle spectrometer. The wavelength of the emitted energy is element-specific and directly proportional to the concentration.
Fields of Application
The GC detector EPED can be used for the analysis of chlorinated and fluorinated compounds, for example in PFAS analysis (per- and polyfluorinated alkyl substances). In addition to brominated flame retardants, further applications include the analysis of sulfur-containing pesticides, the sulfur content of gasoline and diesel, and many others.
Features
- element-specific GC detector for halogens and sulfur
- linear range over 3-4 decades and equimolar response
- Echelle gratings for high wavelength precision and exact element assignment
- detection limits in the range of 0.33 to 4 pg/s
- robust and low-maintenance detector for routine analysis and research