Gas Chromatography–Mass Spectrometry (GC-MS)

Gas Chromatography-Mass Spectrometry (GC-MS) is a technique that combines gas chromatography and mass spectrometry to identify and quantify compounds in complex samples.

Industrial gases serve as carrier gases, fuel gases, and makeup gases in GC-MS systems. These gases must meet strict purity requirements to prevent contamination and interference with analytical results.

High-purity gases ensure accurate results, extend column life, reduce background noise, and improve detection limits in GC-MS analysis. They also minimize system downtime and maintenance costs by preventing contamination.

Helium is the main carrier gas in GC-MS that transports sample compounds through the chromatographic column for separation and into the mass spectrometer for detection.

Hydrogen is used as a carrier gas alternative to helium and as a fuel gas for flame ionization detectors (FID) in GC systems. It provides faster analysis and improved efficiency while maintaining excellent performance.

Nitrogen serves as a makeup gas to optimize detector performance, as a purge gas to maintain system cleanliness, and as a carrier gas for specific applications. It helps ensure consistent flow rates and protects sensitive components from atmospheric contamination.

GC-MS applications typically require ultra-high purity or research grade gases with purity levels of 99.999% or higher. Trace impurities like oxygen, moisture, and hydrocarbons must be kept to extremely low levels to prevent baseline drift and peak contamination.

Common gas mixtures used in GC-MS include 1 ppm to 100 ppm levels of volatile organic compounds (VOCs) in nitrogen or air, such as benzene, toluene, ethylbenzene, and xylene (BTEX). Methane in argon, sulfur hexafluoride, and perfluorotributylamine (PFTBA) are also widely used.