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Optimizing the MS Detector with Your Analyte in APCI/MS Mode
Optimizing the Tune of the MS Detector Automatically in APCI/MS Mode
Thermo Electron Corporation
LTQ XL Getting Started
123
Optimizing the Tune of
the MS Detector
Automatically in
APCI/MS Mode
You can optimize the tune of the MS detector automatically for APCI
operation.
The most important parameters that affect the signal quality during
APCI/MS operation are vaporizer temperature, ion transfer tube
temperature, API gas flows, and solution flow rate. If any one of these
parameters changes, you must re-optimize MS detector parameters. (You
can use the Semi-Automatic tune procedure to tune the MS detector on
individual parameters.)
Use the following procedure to automatically optimize the MS detector on
the reserpine peak at
m/z
609.2 at your particular flow rate, for example,
400
μ
L/min. (See
for guidelines about flow rates and
temperatures.)
Automatically optimize the MS detector
1. On the Control/Scan Mode toolbar, click
Tune
to display the
Automatic tuning page. See
.
2. In the What to Optimize On group box, select the Mass option button
to make active the Mass spin box.
3. In the Mass spin box, type
609.2
to specify that you want to tune on the
peak at
m/z
609.2.
4. Verify that the Divert/Inject valve is in the Detector position, as follows:
a. Click the
Divert/Inject Valve
button to open the Divert/Inject
Valve dialog box.
b. Select the
Detector
option button, and then click
Close
to return to
Tune Plus.
5. Start the automatic tuning procedure from the Tune dialog box, as
follows:
a. Click
Start
.
A message box displays the following message:
Please ensure that the 500 microliter syringe is full.
Ensure the syringe pump contains at least 450
μ
L of the 125 fg/
μ
L reserpine
tuning solution.
b. Click
OK
to close the message box, and return to the Tune Plus
window.