Gas chromatography (GC) separates individual components according to their vapour pressures and solubility inside the GC column material. Mass spectrometry (MS) identifies the eluted components by their ionized molecular fragmentation patterns. With proper selection of GC column material and GC temperature programming procedures, the method can be adapted theoretically for analyzing different volatile organic compounds. GC-MS is an instrumental technique, comprising a gas chromatograph (GC) coupled to a mass spectrometer (MS), by which complex mixtures of chemicals may be separated, identified and qualified. It is a useful technique for the determination of volatile and semi-volatile, thermally stable compounds. In addition, the MASTER TD meets and exceeds specifications given in the international standards.
• Mass calibration stability: RF-only field is stable for weeks to several months at constant analyzer temperature and helium flow
• Transfer line temperature: Independent control; max. 350 °C
• Manifold temperature: Independent control; max. 120 °C
• Analyzer temperature: Independent control; max. 250 °C
Thermal Desorption Technique is becoming the alternative method to traditional solvent extraction offering many advantages like a considerable increase in sensitivity (up to 1000-10000 times), and a higher percentage recovery (over 95% for all volatile substances). The master TD, combined with the GC, is the solution of choice for air monitoring (indoor, workplace, and ambient air) and for the analysis of soil, polymers, packaging materials, etc.
The 220-MS offers advanced ionization and scanning techniques to enhance selectivity and lower limits of detection. MS reduces matrix influences and provide more detailed structural information.
The Varian 450-GC completes the 220-MS. Varian 450-GC has the following key features:
An addition to the GC-MS an autosampler is provided especially for Tenax tube application, called the Thermal Desorber Unit (TD) from DANI Instruments.
The master TD, combined with the GC, is the solution of choice for air monitoring (indoor, workplace, and ambient air) and for the analysis of soil, polymers, packaging materials, etc.
The inherent sensitivity of chromatography and mass spectrometry makes the combined techniques ideal for the analysis of smells, odors and/or non odorous volatile organic compounds (VOC) emitted from a wide range of products from food to polymers and pharmaceutical to Oil and Gas Sector. One of the most common applications for TD GC-MS is the analysis of odors from indoor or outdoor air.