
Overview of PSD Analysis
Voyager
™
Biospectrometry
™
Workstation User’s Guide 7-9
7
7.1.5 Optimizing the Precursor Ion Selector
The Precursor Ion Selector (called Timed Ion Selector in
Reflector mode) allows you to analyze the ion of interest by
deflecting ions until the time that corresponds to the mass of
the ion of interest. At the time that corresponds to the mass of
the ion of interest, the Precursor Ion Selector voltage is turned
off, and the ion of interest passes to the reflector. After the ion
passes through, voltage is turned on again in the ion selector.
The width of the mass window in which the Precursor Ion
Selector voltage is turned off is determined by the Deflector
Gate Width parameter. The Deflector Gate Width is optimized
for your system when your system is installed. However, you
can increase or decrease the selectivity of the Precursor Ion
Selector by decreasing or increasing the Deflector Gate Width
setting.
CAUTION
Before changing the Deflector Gate Width setting, write
down the current setting. This setting has been optimized
for your system and you may want to reset to the optimized
value.
Smaller width values provide narrower Precursor Ion Selector
resolution. If you set the width too low, fragment ion yield is
compromised due to product ion dispersion that occurs as
ions travel down the flight tube.
To change the width setting, select Hardware Configuration
from the Instrument menu in the Instrument Control Panel,
then click the Timed Ion Selector tab (Figure 7-4).
Comentarios a estos manuales