Thermo Scientific TSQ 8000, Руководство пользователя

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3
Tuning
Tuning the Mass Spectrometer
34 TSQ 8000 Evo User Guide Thermo Scientific
b. EI Standard Quick Tune —A shortened version of the EI Standard Tune
recommended for use when subsequent maintenance tuning is needed after an
EI Standard Tune. This tunes the repeller in conjunction with Q3 to overcome the
effects of matrix buildup in the source. It starts with the last saved tune and sets the
detector sensitivity to generate a
m/z 219 ion with an intensity of 20,000,000 counts.
c. EI SRM Tune —Provides EI tuning and completely retunes the system. This tune
reoptimizes nearly all the parameters affecting the signal. This type of tune performs a
mass calibration, tunes the lenses and resolution, and performs a leak check. Unless
your SOP requires it, this is not the best tune to use on a daily basis because of the
length of time required to run it. This tune is more sensitive for high mass than the
EI Standard Tune, making it more sensitive to many SRM transitions. It sets the
detector sensitivity to generate a
m/z 219 ion with an intensity of 20,000,000 counts
and verifies the correct mass calibration.
d. EI SRM Quick Tune —A shortened version of the EI SRM Tune that is
recommended for use when subsequent maintenance tuning is needed after an
EI SRM Tune. This tunes the repeller in conjunction with Q3 to overcome the
effects of buildup in the source. It starts with the last saved tune and sets the detector
sensitivity to generate a
m/z 219 ion with an intensity of 20,000,000 counts.
e. EI Tune Check —Used to check how well your last tune is performing. As it is the
fastest tune type, it allows you to quickly update the detector sensitivity as the system
gets dirty. This allows the sample intensity to remain constant for longer periods
without running a full retune of the instrument.The daily tune check performs a leak
check, makes sure the mass calibration is correct, and sets the detector sensitivity to
generate a
m/z 219 ion with an intensity of 20,000,000 counts. If your SOP allows it,
you can use this tune to rapidly verify that the previous lens tune is still generating
good spectra.
f. EI Diagnostics Only —Runs a complete set of diagnostics, including a leak check,
and generate a report. No tuning is performed. Uses the parameters from the last
saved tune.
g. EI Target Tune —Starts with the last saved tune and adjusts the ion ratios of the
calibration gas to those expected of classic single quadrupole MS analysis. This tune is
intended to be run after full calibration using an EI Standard Tune. If your SOP was
developed in response to regulatory requirements for classic single-quadrupole MS
analysis, or you require classic single quadrupole spectra for spectral library matching,
use this tune. It also sets the detector sensitivity to generate a
m/z 219 ion with an
intensity of approximately 20,000,000 counts and verifies correct mass calibration.
h. EI Initial Tune —Creates a default tune file. It requires a clean instrument, and it sets
the repeller to 5 V and the quadrupole voltages to low values. This tune is used to
reset parameters for all the other tunes after cleaning the ion source. As a result, use
this tune only when the ion source is clean. The EI initial tune should also be used
when changing from an SRM tune to a standard tune. The EI initial tune has higher
resolution and lower sensitivity than the EI standard tune. This tune starts with the
tune file stored in the instrument at the factory. It then performs a mass calibration
and leak check, sets the repeller to 0 V, and tunes the lenses. The quadrupole offset