Thermo Scientific TSQ 8000, Руководство пользователя

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5
Optimizing Your Method
Modifying an Automatic Tune
Thermo Scientific TSQ 8000 Evo User Guide 105
i. Repeller —Controls how the repeller pushes the ions out of the ionization
region. The voltage applied to this component has a very strong effect on the
energy of the ion beam, which has a strong effect on the resolution and the
intensity. The lower the voltage, the better the resolution. However, higher
voltages will prevent ions from striking the repeller surface, which leads to better
robustness. A clean system typically tunes from 3 to 8 V, although a dirty system
may have the repeller climb as high as 12.5 V. Do not set the repeller any higher.
ii. Lens 1 —Controls Lens 1, which is the first of three lenses that the ions see as
they leave the ionization region. These three lenses act as a focusing element to
maximize the ion beam intensity that is entering the ion guide. This field is
typically set between –35 and –50 V.
iii. Lens 2 —Controls Lens 2, which is the second of three lenses that the ions see as
they leave the ionization region. These three lenses act as a focusing element to
maximize the ion beam intensity that is entering the ion guide. This field is
typically set between 0 and –15 V.
iv. Lens 3 —Controls Lens 3, which is the last of three lenses that the ions see as
they leave the ionization region. These three lenses act as a focusing element to
maximize the ion beam intensity that is entering the ion guide. This field is
typically set between -30 and -35 V.
v. Ion Guide Voltage —Controls the ion guide’s DC offset voltage. It can
potentially help focus the ions into the quadrupole while ensuring that neutral
noise is eliminated. The voltage on this component is mass dependent and
should be set at several different masses. This field is typically set b1 and
–15 V, depending on the mass of the ion.
vi. Ion Guide RF q —Controls the ion guide's RF q (amplitude). This device is
mass dependent and should be set at several different masses. This field can be
tuned between 0 and 2. This device determines the ion guide RF amplitude tune
value which is given as the RF q * (
m/z ).
vii. Ion Guide RF —(This setting is maintained for compatibility with legacy tune
types. For new tune types, Ion Guide RF q is the recommended setting.)
Controls the ion guide’s RF voltage. It can potentially help focus the ions into the
quadrupole while ensuring that neutral noise is eliminated. The voltage on this
component is mass dependent and should be set at several different masses. This
field is typically set between 0 and +5 V, depending on the mass of the ion.
viii. Q1 Voltage —Controls the voltage that pulls the ions into the quadrupole. The
voltage applied to this component has a very strong effect on the energy of the
ion beam, which has a strong effect on the resolution and the intensity. The
lower the voltage, the better the resolution. However, higher voltages will pull
more ions into the quads, which leads to better signal. This field is typically set
between 0 and –5 V.
ix. Q1 Resolution —Adjusts the ratio of the quadrupole DC and RF voltages to
create the resolution required for your analysis. You can set the desired peak
width at a given mass and whether you measure the width at 10% or 50% of the