ibidi Pump System
8.6
Working with Non-Implemented Flow Channels
This section describes the procedure for working with flow channels that are not implemented in the
software. It details how to generate a defined shear stress by means of an example.
Knowledge of how to calculate the wall shear stress in the geometry of the experimental slide is
required.
Principle:
1. Define the shear stress needed for the experiment.
2. Calculate the flow rate required to obtain this shear stress in the specific slide geometry.
3. Measure a calibration curve with the slide and the ibidi Pump System (with Fluidic Unit and
Perfusion Set), showing the dependence between flow rate and pressure.
4. Determine the pressure needed to obtain the correct flow rate.
5. Apply this pressure with the pump, ignoring the values of flow rate and shear stress displayed
in the PumpControl software.
6. Adjust the switching time.
Example:
The sticky-Slide channels are not available in the drop-down menu of the software. The formulas
to calculate the shear stress can be found in the
. The example shows the
procedure for the sticky-Slide
0.4
Luer.
τ
dyn
cm
2
=
η
dyn
·
s
cm
2
·
104.7
·
Φ
ml
min
1. Define the shear stress needed for the experiment: 10 dyn/cm
2
2. Calculate the flow rate required in the sticky-Slide I
0.4
Luer to generate the desired shear stress
using the formulas above. The viscosity of medium at 37°C is 0.0072 dyn s/cm
2
.
Φ
ml
min
=
τ
h
dyn
cm
2
i
η
h
dyn
·
s
cm
2
i
·
104.7
=
10
0.0072
·
104.7
=
13.3
ml
/
min
3. Measure a calibration curve with the ibidi Pump System. Measure the respective flow rates you
obtain with pressure values from 5 mbar to 95 mbar, using the setup that was chosen (Slide and
Perfusion Set).
Apply the respective pressure and switch the valves manually. Measure the time required for
the medium to flow from the 6 ml to the 4 ml mark on the syringe (around equilibrated medium
levels).
Display the values in a graph and calculate a trend line.
Version 2.6 (May 12, 2022)
68
Instruction Manual
