Applied Biosystems 7900HT User Manual page 132

Chapter 4 Operating the Instrument
4-18 Applied Biosystems 7900HT Fast Real-Time PCR System and SDS Enterprise Database User Guide
September 1, 2004 11:39 am, CH_Basic.fm
4. When the cover has fully opened, remove the buckets from the centrifuge, then
remove the card holders from the buckets.
5. Remove all Low Density Arrays from the buckets by gently lifting them by their
carrier sides.
6. Examine the Low Density Arrays to determine whether filling is complete.
The amount of cDNA sample or control remaining in the fill reservoirs should
be uniform and consistent from reservoir to reservoir.
• If there is excess cDNA sample or control remaining in a fill reservoir (as
shown below), filling is incomplete. Proceed to the next step.
• If a fill reservoir is completely drained (as shown below), it is possible that
some wells were not filled properly.
– The Low Density Array should not be processed further. Use another
Low Density Array.
– Alternatively, you can process the Low Density Array further; however,
you should void the results for the affected fill reservoir (sample).
7. Evaluate the filling as follows:
If all fill reservoirs are...
not uniform after the first
centrifuge cycle
not uniform after the
additional centrifuge cycle
Do not exceed 1200 rpm or accumulated centrifugation times of
IMPORTANT!
more than 3 min. Excessive centrifugation speeds and times may deform the
Low Density Array.
DRAFT
Then...
the Low Density Array may be centrifuged again in the
same manner as before for 1 additional min.
• The Low Density Array should not be processed
further. Use another Low Density Array.
• Alternatively, you can process the Low Density Array
further; however, you should void the results for the
affected fill reservoir (sample).