and less often, protonated molecules [{M}+H]+. The technique was first reported by Beckey in 1969. It is also the first ionization method to ionize nonvolatile and thermally labile compounds.
Protonated molecules [{M}+H]+ are utilized less frequently; this technique was initially reported by Beckey in 1969. It is the first ionization method to ionize nonvolatile and thermally unstable compounds.