ThermoFisher Scientific Vanquish VC-D50, Operating Manual

Page: 100 / 188

6 • Operation
Page 100 Fluorescence Detectors (VC-D50, VC-D51, VF-D50, VF-D51)
Operating Manual
Setting the Multi-Channel Performance
In multi-channel mode, you can select a measuring performance (multi-
channel performance) to determine whether the measurement is
performed faster, but with more noise, or whether minimum noise is
required, which means a longer measuring time and lower data
collection rate. The possible values are:
UltraFast , Fast , Standard ,
LowNoise , UltraLowNoise .
Response time and data collection rate for multi-channel mode are
determined automatically on the basis of the selected multi channel
performance and the selected parameters, and adjusted each time
wavelengths are switched during the measurement.
Using multiple channels in the Chromeleon software
Use the Instrument Method Wizard (Advanced mode) to define the
parameter settings for all channels and the multi-channel performance.
See also
2 Determining the Optimum Excitation and Emission Wavelength
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page 107)
6.7.3 Zero Order Mode
In Zero Order Mode, the grating of the emission monochromator reflects
the entire emission spectrum of the sample onto the PMT, rather than
only a single wavelength. The excitation monochromator is set to a
single wavelength as usual.
Use this mode during method development, if you do not know the
retention times and emission wavelengths of the various substances in
your sample. As the entire range of emission wavelengths is acquired,
you can determine the retention times of all substances in a single run,
as long as the substances can be excited at the selected excitation
wavelength.
TIP
Use the filter wheel setting (VF detectors only) to cut off undesired
wavelengths. For example, set the filter wheel setting to 370 nm to
restrict the emission wavelength range to wavelengths above the filter
wavelength.
The Zero Order Mode is also suitable for samples that emit light in an
exceptionally broad band. In this case, the measured intensity is higher
in Zero Order Mode than under normal operation where most of the
emitted light is discarded by the emission monochromator. This might
allow you to achieve a better limit of detection.