Agilent Technologies NovoCyte Quanteon Operator's Manual page 40

Introduction
Figure 13. Hydrodynamic Focusing and Core Diameter under Different Sample Flow Rates
Having at most one cell or particle moving through a laser beam at a given time is
critical for flow cytometry. This is achieved by the hydrodynamic focusing process.
Proper operation of fluidic components is critical for particles to intercept the laser
beam properly. Always ensure that the fluidics system is free of air bubbles, cell
debris, and other contaminants. Choosing the appropriate sample flow rate for
your experiment is important for obtaining good quality data.
A higher sample flow rate is generally used for qualitative measurements such
•
as immunophenotyping. The data is less resolved but is acquired more
quickly.
A lower flow rate is generally used in applications where greater resolution and
•
quantitative measurements are critical, such as DNA content analysis.
There are three standard sample flow rate settings in Agilent flow cytometer,
which is Slow (e.g. 14 μL/min), Medium (e.g. 35 μL/min) and Fast (e.g. 66 μL/min),
corresponding to approximately 7.7 μm, 12.2 μm and 16.8 μm core diameter
respectively. The sample flow rate can also be continuously adjusted in
NovoExpress software from 5 μL/min to 120 μL/min, which corresponds to a core
diameter of 4.6 μm to 22.7 μm. The sheath flow rate is fixed at 6.5 mL/min.
40 NovoCyte Quanteon Flow Cytometer Operator's Guide