Thermo Scientific TSQ 8000, User Manual

Page: 94 / 150

4
Creating a Method
Creating a MS Instrument Method
72 TSQ 8000 Evo User Guide Thermo Scientific
v. Under Acquisition Options , select the Allow for Asymmetric Acquisitions
check box to add extra time to the beginning or end of an acquisition window
without affecting other timing in your scan. When you select this option,
Pre-width and Post-width columns are added to your method. Enter the extra
times in these columns.
Select the Allow Dwell Time Prioritization check box to increase the dwell
times for selected scans. The choices for each scan are Normal or High . Giving a
scan high priority increases its dwell time by the value you set in the High
Priority Multiplier box.
vi. Under Full Scan , you indicate if a Full Scan is to be run along with SIM and
SRM. The Mass Range, Scan Time, Start and End Time can be set after the Use
Full Scan box is checked. The full scan time will reduce the SRM/SIM time
without increasing the total scan time. If you only want to use full scan for part
of your method, you can enter full-scan start and end times.
b. Use the options in the Instrument Settings panel to further adjust your method.
i. Use Tune File to select a tune file or files to be used for this scan. If you are using
EI, only the Tune File(+) pull-down menu is available. If you are using negative
CI, select a tune file from the Tune File(-) pull-down menu. Choose
AutoTune_NCI to use the most recent negative CI automatic tune file you
created in Chapter 3, “Tuning.” If you are using positive CI, select a tune file
from the Tune File(+) pull-down menu. Choose AutoTune_PCI to use the most
recent positive CI automatic tune file you created in Chapter 3, “Tuning.” The
software defaults to the most recent AutoTune_NCI or AutoTune_PCI tune file
you created.
ii. In the Detector Gain area, set the detector gain. Select the U se Last Tuned
Detector Gain option to indicate that you want to use the detector gain set in
Auto Tune. If you do not need to use the gain set in Auto Tune, then you can set
the gain manually. Higher gains give larger signals, but may shorten the lifetime
of the detector when concentrated samples are detected. To manually set the
detector gain, select the
Use Specified Detector Gain radio button and enter the
desired value in the Detector gain box.
iii. Use the Emission Current box to set the emission current used during the
acquisition. For optimal analytical performance and stability, use the emission
current at which the system was tuned. However, if you want to use a different
emission current, select the
Use Specified Emission Current radio button and
enter a value in the Emission Current (μA ) box. A high emission current will
lead to the production of more ions, but the interaction of too many ions in the
source can cause a degradation in the resolution and signal. The margin of error
is ± 0.5 μA.
Note This option is only available when the method optimizer is not active.
Tip Click the arrow at the top right of the Scan Settings panel to collapse or
expand the panel.