FiT SUPER SESI, Руководство пользователя

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SUPER SESI, by FIT User manual, Revision 2.0
Figure 23. Detail of the positioning marks for the electrospray tip
CAUTION do not pass the zero. Doing so will introduce the silica capillary in the inlet
capillary of the mass spectrometer. This can cause the silica capillary to break. Resulting
debris could be ingested by the mass spectrometer and damage it.
Rise the ion source voltage. This voltage is provided by the mass spectrometer, and it is
controlled by the mass spectrometer software. Refer to the user manual of your mass
spectrometer to rise this voltage. The SUPER SESI requires a typical voltage between 2.5 kV and
3.5 kV. The SUPER SESI can be operated in negative and positive modes irrespectively.
INTERESTING NOTE SUPER SESI uses the flows provided by the mass spectrometer. The SHEATH
GAS is used to pressurize the vial to create the electrospray.
To pressurize the electrospray vial holder first rise the SHEATH GAS on the MS-software to
provide a continuous flow into SUPER SESI.
To rise pressure first open the valve 1 (up position), and set the pressure with the pressure
regulator. Note that the high-pressure circuit has some inertia. You will see that the pressure
display rises slowly when the regulator is actuated until it reaches a plateau.
Once the pressure is raised, the liquid starts to flow through the capillary. It usually takes about
one to two minutes for it to reach the tip of the silica capillary. At this point, the electrospray
will be formed. You will see a positive reading in your nano-amperemeter and the background
spectra in your mass spectrometer.
INTERESTING NOTE It is strongly advised to verify that the electrospray is stable. The stability of
the electrospray can be evaluated by monitoring the intensity of the signals detected by
the mass spectrometer, and by visually inspecting the nano-amperemeter. You can fine
tune the electrospray voltage, the electrospray pressure, and the position of the tip to
improve the stability. The stability of the electrospray can also be affected by the
temperature of the ionization chamber. If this temperature is above the boiling point of
the liquid, or if it is too close to it, the electrospray might be very unstable. If this is your
case, lower it by 5ºC.
Introducing samples and acquiring data
The data is acquired with your mass spectrometer. To acquire data, refer to the user manual of
the mass spectrometer.