Mass Reference Solution - Agilent Technologies G1992A User Manual

Agilent G1992A Nanospray Ion Source
User Guide
2

Mass Reference Solution

To prepare the Low Mass IRM stock solution
To prepare the IRM working solution
To apply the IRM solutions
To enable reference mass correction
To clean the wick and wick cover
Reference mass solutions are only used with the 6200 Series TOF LC/MS and
the 6500 Series Q-TOF LC/MS. The 6400 Series Triple Quadrupole LC/MS does
not use these solutions.
When you take accurate mass measurements on a TOF or Q-TOF instrument,
the addition of compounds which ionize under the analysis conditions and
provide known accurate mass values ("reference masses") in real time allows
you to correct the mass values in the acquired spectra for short-term
variations.
This chapter describes how to use reference masses with TOF or Q-TOF
instruments outfitted with a Nanospray Ion Source and operated in positive
ion polarity. In summary, solutions are applied to an absorbent wick on the
top inside of the source, and then the IRM compounds slowly evaporate and
are ionized, providing signals for correction of the mass assignments.
The solution of internal reference mass standard(s) in acetonitrile (ACN) is
applied to the wick and allowed to dry. Then the high mass solvent (FC-70) is
applied. The use of FC-70 is optional. Signals from the IRM compounds are
acquired without its use, but the response is more uniform and lasts longer
when it is used.
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