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SIFT-MS is an ideal tool for high-throughput and real-time gas analysis applications.

Selected ion flow tube mass spectrometry (SIFT-MS) is a form of direct mass spectrometry that analyzes trace amounts of volatile organic compounds (VOCs) and inorganic gases in air. Real-time, quantitative analysis is achieved by applying precisely controlled soft chemical ionization and eliminating sample preparation, pre-concentration and chromatography.

There are three elements of the SIFT-MS technique:

  • Reagent ion generation and selection. The eight SIFT-MS reagent ions H3O+, NO+, O2+, O-, O2-, OH-, NO2-, and NO3- are all formed by microwave discharge through moist or dry air. The reagent ion of choice is then selected using a quadrupole mass filter.
  • Analyte ionization. The selected reagent ion is injected into the flow tube and excess energy is removed through collisions with the carrier gas. The sample is then introduced at a known flow rate and the reactive compounds it contains are ionized by the reagent ion to form well-characterized product ions.
  • Analyte quantitation. Product ions and unreacted reagent ions are sampled into a second quadrupole mass spectrometer. Utilizing Syft’s compound library, the software instantaneously calculates each analyte’s absolute concentration.


  • Instantaneous, quantitative analysis of air and headspace with very high sensitivity and selectivity.
  • Simultaneous analysis of chemically diverse VOCs (e.g. aldehydes, amines and organosulfurs).
  • Direct analysis of high humidity samples.
  • Simplicity of operation.
  • Simple integration with existing infrastructure.
  • Low maintenance and long-term stability.


Automation Applications
Automation has been widely utilized by traditional chromatographic techniques for many years, enabling instrumentation to be productive 24/7