摘要 |
The present invention concerns a system and method of mass spectrometry, comprising the following steps: a. ionising an analyte to form a precursor ion (A) having a mass-to-charge ratio (m/z), in which m represents the mass and z the atomic number; b. activating the precursor ion (A) by interaction with a beam of neutral species, ions, electrons or photons, having an energy chosen on the basis of the physicochemical properties of the precursor ion, said activation being suitable for producing a product ion (B, C) having the same mass m as said precursor ion (A) and an atomic number z' such that z' is a non-zero integer different from z, z' preferably being chosen from z+1, z+2, z+3, z-1, z-2, z-3, the product ion being formed by ionisation, electron detachment, electron capture or transfer without fragmentation; c. separating the product ion (B, C, E, F) having a predefined mass-to-charge ratio (m/z'); d. detecting said product ion (B, C) having the predefined mass-to-charge ratio (m/z'). |