Patent attributes
In some embodiments, a tandem (MS/MS) mass spectrometry method includes selecting a collision-induced dissociation (CID) voltage amplitude and a q-parameter value for a quadrupole ion trap to optimize a daughter ion fragmentation process for a given parent ion mass-to-charge (m/z) ratio. The q and CID voltage values may be selected according to a look-up table and/or using approximate analytical expressions. The correspondence between m/z values and (q, CID) value pairs may be established by pre-measurement calibration. A fragmentation-optimized q value may be computed according to m/z, and a CID voltage value may be determined according to the computed q value. A user may also force q to another value, for example in order to facilitate trapping of a desired daughter ion mass range, and the controller computes a CID voltage value according to the forced q value.
