Reagent gas

{
  "id": "MLC-T-CHM-009990",
  "term": "Reagent gas",
  "field": "Chemistry",
  "definition": "A gas introduced into an ion source or ion trap of a mass spectrometer to produce reagent ions through electron ionization. These reagent ions then react with analyte molecules via chemical ionization, a soft ionization technique that produces less fragmentation than electron ionization. Methane and ammonia are two gases frequently used for this purpose in chemical ionization mass spectrometry.",
  "subject": "Analytical Chemistry",
  "see_also": [
    "collision cell",
    "ion trap",
    "reagent ion"
  ],
  "references": [
    "PAC, 2013, 85, 1515. 'Definitions of terms relating to mass spectrometry (IUPAC Recommendations 2013)' on page 1583 (https://doi.org/10.1351/PAC-REC-06-04-06)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/reagent-gas/"
}