Thermo Scientific AMQAF2000, Руководство пользователя

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Observation Possible cause Recommended action
Incorrect concentration for the
Countess
™
test beads
Beads were not suspended in
solution or mixed correctly. The beads can settle quickly in solution, which
will affect the concentration reading.
Vortex the bead stock on high for a full 30
seconds to resuspend, and add 10 µL of the
bead suspension to 10 µL of trypan blue without
delay.
Pipet the bead and trypan blue mixture up and
down several times to make sure it is well mixed
and immediately load 10 µL into the slide.
Variable counts for the same
sample of cells Pipetting was done incorrectly. If you are pipetting different samples from the
same cell sample, the variability could be due to
pipetting or mixing.
Use recently calibrated pipettors and make sure
that the cells are well suspended by pipetting
up and down several times before adding trypan
blue.
Variable counts when
performing replicate counts of
the same slide Slide was mishandled or viewed
differently multiple times. If you are counting replicates of the exact same
slide, visually inspect that all cells are counted
correctly in the image.
There may be a slightly different field of view
each time a slide is inserted. Depending on the
concentration and uniformity of the cells, this will
cause some variability when performing replicate
counts of the same slide, although it should be
less than 10%.
When counting fewer cells, a small field of view
change for only a small number of cells can
have a larger affect. Count cells at a higher
concentration to reduce variability
Make sure you do not shake or agitate the slide
between counts.
Abnormally high percentage of
dead cells or live cells counted
as dead
Focus was not correct for the
sample. Ensure that the cells are focused correctly so
that live cells have bright centers and dead
cells are dark throughout. If the cells are not
well focused and look dark on the screen, the
Countess
™
3 FL cell counter will count them as
dead cells.
Live cells vs dead cells were
difficult to distinguish. If cells are well focused, have bright centers, and
are being counted as dead, confirm that they
are within the appropriate cell size range and try
adjusting the settings.
Cells were exposed to trypan
blue for too long. If cells are exposed to trypan blue for a long
period of time, viability could be affected so slide
should be prepared and counted fresh each
time for best results.
Appendix A
Troubleshooting
Clean the cell counter
A
Countess ™ 3 FL Automated Cell Counter User Guide
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