Existence of self chemical ionization in the ion trap detector

Abstract

°Cdoes not destroy HNOg, however. The presence of up to x/2 mL of HNOg does not interfere with the fluorometric analysis of Se. The 2 • 01 in the stabilizing solution helps minimize oxidation of the DAN by HNOg (9). ACKNOWLEDGMENTThe authors thank D. Scherer and A. Jacobson for providing the tomato leaf sample and the value for its Se content obtained by using the HN03/HC104 digestion method.

Use of a hand-portable gas chromatograph–toroidal ion trap mass spectrometer for self-chemical ionization identification of degradation products related to O-ethyl S-(2-diisopropylaminoethyl) methyl phosphonothiolate (VX)

“…In addition to loss of mass resolution, it is known that space charging can result in lower effective radiofrequency (RF) amplitude experienced by trapped ions as the range of m/z values is scanned during analysis. This causes ions to be ejected from the trap inappropriately late when scanning from low to high m/z, leading to incorrectly assigned (higher) m/z values [12].…”

Formation of protonated phosphonates in the ion‐trap mass spectrometer under electron impact conditions

“…' The presence of heteroatoms such as oxygen or nitrogen in aliphatic molecules can favour this process called 'self ionization'. By using mass spectrometers that allow ion storage, such as ion-trap instruments and ion cyclotron resonance mass spectrometers, 'self chemical ionization' is more easily observed since longer residence times result in ion/molecule collisions even at low sample pressures.2," 4,5 Phosphonate compounds are characterized by an [M + l]+/(M+') ratio larger than that predicted for the natural isotopic ratio.6 For instance, diethylmethylphosphonate was characterized by a low abundance M+' ion (mlz 152) accompanied by a signal at m/z 153 (30% of M+*) (see Fig. 2).…”

Examination of the Best Pressure Range for Ion/Molecule Reactions of Anthraquinones in an External Source Ion Trap Mass Spectrometer

“…First, in the traditional ITMS, self-chemical ionizations were observed, typically 26,27 resulting in the formation of [M + H] + ions. But in the GCQ, only the ion/molecule reaction products and DME reagent ions were allowed to enter the ion trap; all neutral molecules were left in the source region.…”