Hydrogen as a GC/MS carrier and buffer gas for use in forensic laboratories

• Helium is quickly becoming an expensive and limited commodity.
• Hydrogen as a carrier gas increases the overall analysis speed and resolution.
• Ion volumes of diameters 1, 2, 4, 6, 8, and 10 mm were used to compare intensities.
• 10 mm ion volume showed highest intensities for illicit drug and energetic materials.
• Hydrogen gas may cause slight variations in the mass spectra, usually m/z 1 shift.

A custom set of ion volumes was manufactured in order to investigate the gain and byproducts using hydrogen as a buffer gas following electron ionization in a quadrupole ion trap mass spectrometer as compared with helium. Analyses of illicit drugs such as cocaine, codeine, and oxycodone, and explosives such as TNT, RDX, and HMTD with ion volume exit orifices of 1 mm, 2 mm, 4 mm, 6 mm, 8 mm and 10 mm were performed using GC/MS. Strong similarities between hydrogen and helium spectra of illicit drugs and explosives provide evidence that hydrogen can be used effectively as a buffer gas in an ion trap mass spectrometer.

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