ChemoMetec NC-100 - Manual (Page 40)

6 Total and viability count
24
available to load the NucleoCassette. It is important that the sample must be
representative of the cell suspension. Throughout the examples in this User’s Guide a
sample size of 200 µl is used.
Add 200 µl of the Lysis buffer to the cell sample and mix thoroughly by turning the vial
upside down 5-10 times. Alternatively you can use the pipette.
Add 200 µl of the Stabilizing buffer and mix thoroughly. This mixture is called the
Stabilized lyzate .
Load the NucleoCassette with the stabilized lyzate immediately after mixing; immerse
the tip of the NucleoCassette in the stabilized lyzate and press the piston gently, see
Figure 24. The piston is pressed down to the level of the finger grips. It is important to
press the piston down slowly and to make sure that the tip is immersed in the stabilized
lyzate to avoid air bubbles in the flow system.
The stabilized lyzate is stable for several minutes. Therefore, it is not necessary to load
the NucleoCassette immediately after the preparation. But it is very important that the
lyzate is thoroughly mixed just before the NucleoCassette is loaded in order to assure
sample homogeneity.
Figure Figure Figure Figure 24 24 24 24 Load the NucleoCassette by immersing the tip in the stabilized lyzate and
gently press the piston.
Open the lid of NucleoCounter and insert the loaded NucleoCassette. Then close the lid
and press “Run”. The lid has to be closed during the analysis to eliminate any external
light from the NucleoCassette chamber. External light may compromise the quality of
the analysis.