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Analytical Laboratories Applications

GC with Electron Capture Detector (GC-ECD)

Gas Chromatography – Electron Capture Detector or GC-ECD is a technique used to analyse halogenated compounds and is primarily used in the environmental, forensic and pharmaceutical markets. Within an ECD, when certain molecules pass by the detector, they capture some of the electrons in the sample and this reduces the current measured. The compensation for this reduction is recorded as a positive peak.

As common with other GC techniques, a carrier gas is required with low Water and Oxygen impurities since Water and Oxygen can interact with the stationary phase and cause significant problems such as high baseline noise and column bleed in the output gas chromatogram which both reduces the analyser sensitivity and decreases column lifetime. Oxygen and Water impurities can also oxidise the radioactive Nickel source and reduce the detector response. In addition the carrier gas must have exceptionally low levels of Halocarbons as the ECD is extremely sensitive to these compounds.

The ECD also requires a make-up gas if Helium is used as the carrier gas since this serves to provide the electrons which are not contained within the Helium. The routine calibration of the analyser using a calibration mixture is common.

Our range of Experis® ultra high purity gases and patented BIP® technology offer you the optimum gas for your GC-ECD requirements. Don’t forget that your choice of cylinder equipment also affects your analytical results. Our range includes high quality cylinder regulators, manifolds, valves and purge systems which will help to optimise the smooth operation and accuracy of your analysis. For GC-ECD it is important to only use equipment that is approved for use with ECD.

The recommended gases and equipment for this application are listed below. Please note that our recommendation is based on common analytical requirements, so you may require a higher purity grade if analysing to lower concentrations or be able to use a lower purity grade if analysing to higher concentrations. If you require any additional advice on the right purity grade for your needs, please contact us. 

Other Applications

Product NameDescription/BenefitsDownloads
Gases

Helium BIP® ECD gas

Due to the sensitivity of the ECD detector to Halocarbons, Helium BIP® ECD gas with its ultra low Halocarbon levels is the perfect carrier gas to ensure accurate analyses.

Due to the sensitivity of the ECD detector to Halocarbons, Helium BIP® ECD gas with its ultra low Halocarbon levels is the perfect carrier gas to ensure accurate analyses.

Nitrogen BIP® ECD gas

Due to the sensitivity of the ECD detector to Halocarbons, Nitrogen BIP® ECD gas with its ultra low Halocarbon levels is the perfect carrier and makeup gas to ensure accurate analyses.

Due to the sensitivity of the ECD detector to Halocarbons, Nitrogen BIP® ECD gas with its ultra low Halocarbon levels is the perfect carrier and makeup gas to ensure accurate analyses.

Process Mixtures

An Experis® gas mixture of Methane in Argon is the ideal makeup gas in GC-ECD when Helium is used as a carrier gas.

An Experis® gas mixture of Methane in Argon is the ideal makeup gas in GC-ECD when Helium is used as a carrier gas.

Equipment

Cylinder Regulators

Essential for reducing the gas pressure at the cylinder source, our range of high-quality cylinder regulators are available in single- or double-stage, a variety of materials such as brass, stainless steel and Monel®, and various inlet and outlet pressure ranges.

Essential for reducing the gas pressure at the cylinder source, our range of high-quality cylinder regulators are available in single- or double-stage, a variety of materials such as brass, stainless steel and Monel®, and various inlet and outlet pressure ranges.

Line Regulators

Essential for reducing the gas pressure in a pipeline, our range of high-quality line regulators are available in either brass or stainless steel, and various flowrate and outlet pressure ranges.

Essential for reducing the gas pressure in a pipeline, our range of high-quality line regulators are available in either brass or stainless steel, and various flowrate and outlet pressure ranges.

Manifolds

Essential for ensuring a batch or continuous supply, our range of high-quality manifolds can connect up to six cylinders, can provide manual or semi-automatic changeover and are available in brass or stainless steel.

Essential for ensuring a batch or continuous supply, our range of high-quality manifolds can connect up to six cylinders, can provide manual or semi-automatic changeover and are available in brass or stainless steel.

Pressure Gauges

Our high-quality, accurate pressure gauges are available in brass, stainless steel or Monel® for a wide variety of pressure ranges.

Our high-quality, accurate pressure gauges are available in brass, stainless steel or Monel® for a wide variety of pressure ranges.

Purge Systems

Purge systems are essential for eliminating impurities in and/or operator exposure to the gas when changing over cylinders. Our high-quality cross-purge, self-purge and T-purge systems are available in a variety of materials for the handling of pure, toxic, corrosive and flammable gases.

Purge systems are essential for eliminating impurities in and/or operator exposure to the gas when changing over cylinders. Our high-quality cross-purge, self-purge and T-purge systems are available in a variety of materials for the handling of pure, toxic, corrosive and flammable gases.

Valves

Our range of high-quality check valves and relief valves are available in brass or stainless steel and a variety of connection sizes for the connection of cylinders to equipment.

Our range of high-quality check valves and relief valves are available in brass or stainless steel and a variety of connection sizes for the connection of cylinders to equipment.

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