Peak Detection

Max Charge State

and Max Isotope #

set correctly

When the Max Charge State and Max Isotope # are set correctly (in the example shown in Figure 3-7,both are set to 4), the neurotensin 558 m/z isotope cluster contains four peaks at charge state 3. Peaks are 0.33 m/z apart (Figure 3-7).

Max Charge State

set too low

Figure 3-7 Max Charge State and Max Isotope # Set

3

Correctly for Neurotensin

 

When the Max Charge State is set too low, the charge state for all peaks may not be correctly determined. In this example with the Max Charge State set to 2, only the first and fourth peaks are labeled with charge states (Figure 3-8 on

page 3-34). This is because the software:

•Checks for peaks at 0.5 m/z from each peak (charge state 2 evaluation).

•Finds no peaks and checks for peaks at 1 m/z from each peak (charge state 1 evaluation).

•Finds one peak pair at 558.3 m/z and 559.3 m/z and labels these peaks as charge state 1.

•Does not find a match for peaks at 558.6 m/z or 558.9 m/z, so these peaks are considered to have no calculated charge, and are not labeled with a charge state (Figure 3-8 on page 3-34).

Data Explorer™ Software User’s Guide

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