Beckman Coulter Navios, Instructions For Use Manual

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Quality Control
QC Processes
Discrimination Parameter
The various parameters produce differences in signals ranging from robust to weak signals which
in turn affect the amount of noise in the baseline. The discriminator is applied to the parameter of
your choice, based on your application.
Discriminator Value
A threshold value is applied to the selected parameter signal to control the amount of background
that is measured. Setting the discriminator too low could include a higher amount of debris while
a setting that is too high might eliminate the desired events. See
Discriminators , for information on
selecting and modifying discriminators.
Flow Rate
The flow rate governs the events per second that pass by the flow cell. The concentration of the
particle of interest should be considered when selecting a flow rate so that coincidence (doublets)
is minimized. Generally, the faster the flow rate, the higher the probability for creating coincidence
and higher CVs (broadening of the peak). See
Flow Rate , for instructions on changing the flow rate.
See Figure 3.9 in the Time-Of-Flight Signal section for an example of using the Time of Flight
parameter to detect coincidence.
Voltages and Gains
These settings are used to position the signal for each parameter in the desired position. See
Cytometer Control Acquisition Setup Tab for instructions on changing signal voltages and gains.
Plot Selection
There are several plot types available to view data: bi-variate (dot plots/density plots) and
histograms. Ability to view data to affirm appropriate cytosettings (including voltage, gain and
discriminator assignment) is determined by parameter assignments to the selected plots. See
Plots
Menu , for instructions on creating plots.
Regions and Gating
Regions and gates allow for statistical information to be generated from the data set. Creation and
placement or regions and gate assignments must be verified for the dataset. See
Analysis Menu , for
instructions on creating and modifying regions and gates.
QC Processes
The chart below shows which QC materials are needed for each QC process.