Waters Xevo TQD, Руководство оператора, обзор и техническое обслуживание

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Sample inlet 1-19
Constant neutral loss mode
Constant neutral loss mode detects the loss of a specific neutral fragment or
functional group from an unspecified precursor(s).
The scans of MS1 and MS2 are synchronized. When MS1 transmits a specific
precursor ion, MS2 “looks” to see whether that precursor loses a fragment of a
certain mass. If it does, the loss registers at the detector.
In constant neutral loss mode, the spectrum shows the masses of all
precursors that actually lost a fragment of a certain mass.
Constant neutral loss mode:
Typical application
You typically use constant neutral loss mode to screen mixtures for a specific
class of compound that is characterized by a common fragmentation pathway,
indicating the presence of compounds containing a common functional group.
Sample inlet
Either of two methods delivers solvent and sample to the installed probe:
• An LC system, which delivers the eluent from an LC analysis.
• IntelliStart Fluidics system, which uses onboard solutions to automate
instrument optimization. You can deliver solutions by direct or
combined infusion.
MS1
Scanning
(synchronized with MS2) Collision cell
Fragmenting
precursor ions and
passing all masses MS2
Scanning
(synchronized with MS1)