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Introduction
What Types of Experiments Can I Perform with the LTQ XL MS Detector?
Thermo Electron Corporation
LTQ XL Getting Started
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peptide in a tryptic digest). A Neutral Loss Ion Mapping experiment can
step through each product mass in the mixture. The experiment searches for
evidence of the loss of a neutral moiety of mass 80 u.
A Parent Ion Mapping experiment identifies all the ions that produce a
particular molecular ion that you specify. For example, if you specify a
product ion mass of
m/z
50, a Parent Ion Map includes all the parent ions
that yielded the specified product ion,
m/z
50.
A Data-Dependent Zoom Map is an Ion Mapping experiment that collects
ZoomScan data on every scan interval in a mass range that you specify, as
well as Data-Dependent MS/MS product spectra on every mass above an
intensity threshold.
The results of any of the Ion Mapping experiments can be viewed in the
Xcalibur Qual Browser window.
Ion Tree Experiments
In an Ion Tree experiment, the LTQ XL MS detector can collect MS
n
data
automatically. You can specify a particular parent ion for fragmentation, or
you can let the LTQ XL MS detector find the parent ions automatically and
fragment them to any level between MS
2
and MS
10
. The LTQ XL MS
detector automates the collection of data by deciding what actions need to
occur next for the experiment to progress. See
for an example of an
Ion Tree experiment template.
