Thermo Scientific TSQ 8000, User Manual

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5
Optimizing Your Method
Narrowing the Mass Range
Thermo Scientific TSQ 8000 Evo User Guide 91
Figure 88. Setting the Dwell Time Prioritization
Narrowing the Mass Range
In a full scan analysis, by narrowing your mass range, you can look directly at the compounds
of interest. However, if you are looking at a large number of compounds that have a broad
range of mass fragments, a wide mass range makes sense. To narrow the mass range, refine
your scan parameters to a smaller number. A narrower mass range also allows you to decrease
the scan rate and get the same chromatographic peak sampling. By breaking your MS method
into groups, you can create compound-specific MS settings to optimize your data.
Adjusting the Transfer Line and Ion Source Temperature
If your transfer line temperature is set too low, the less volatile compounds may get stuck in
the transfer line and never make it into the ion source. On the other hand, if your transfer line
is too hot, you could damage the column or cause a thermal breakdown in the compounds
you are analyzing. Typically, aim for the transfer line temperature to be 10 °C (18 °F) over the
highest boiling point of the compounds of interest, but no higher than the maximum safe
operating temperature of the column.
Note The total scan time does not change. If prioritizing some dwell times reduces others
to less the lowest allowed dwell time for your method, try increasing the acquisition
windows.