Qiagen QIAsymphony AS, Руководство по эксплуатации

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QIAsymphony SP/AS Consolidated Operating Guide 12/2017 178
13.7.4 Data analysis errors
Missing or wrong signal for assay standards and assay controls (e.g., internal control)
Error Comments and suggestions
Wrong reagent tube
placed in adapter. If the shape of a tube differs slightly from the required tube type, problems during aspiration
may occur. For instance, a lower volume than expected may be transferred.
No tube placed in a
position on the reagent
holder. If the requested volume is above the liquid-level detection limit, a “not-enough-liquid” message will
appear.
If the requested volume is below the liquid-level detection limit, the QIAsymphony AS will not
recognize a missing tube or the liquid level and will continue with the assay run.
Frozen liquids or closed
tubes. Ensure that the lids were removed from all tubes and that the liquids are completely thawed.
Mix-up of reagent and
assay standard tubes. If the volume is lower than expected, a message will appear indicating that there is not enough
liquid available. Ensure that the reagent and assay standard tubes are correctly positioned.
If the volume is higher than expected, or is below the liquid-level detection limit, the assay run
will continue which may result in missing signals.
Air bubbles or foam
enclosed by liquid. Air was aspirated, perhaps due to bubbles on the surface of the liquid. This may result in
missing signals.
Always ensure that there are no bubbles on the liquid surface. To remove bubbles, centrifuge
the tubes.
Missing sample signal
Error Comments and suggestions
Evaporation. If eluates/assays are left to stand on the QIAsymphony SP/AS instruments for a long time after
a run is complete, evaporation will occur.
Ensure that eluate racks and assay racks are removed immediately when a run is completed.
Wrong volume
information. The eluate volume as defined in the rack file or on the touchscreen is higher than the actual
eluate volume.
The QIAsymphony SP/AS instruments may not be able to transfer the correct sample volumes.
This may result in reduced performance.
Fluctuations in eluate
volumes.
We recommend inspecting the assay rack visually to check for differences in sample volumes.
Large differences in volume indicate that the actual eluate volume differs from the expected
volume and that insufficient eluate was transferred to the assay rack.
If problems persist, reduce the eluate volume.
Wrong rack type selected
for eluate or assay rack. Ensure the correct adapters and consumables, as defined for the current run, are loaded on to
the worktable.
Use of different consumables may result in damage to the QIAsymphony SP/AS instruments and
may cause pipetting problems.
Reactions are not in the
corresponding position on
the assay rack. Ensure that the assay rack and the elution rack are set up with well A1 in the upper left corner.
If 2 elution racks are in use, ensure that the elution racks on slot 1 and 2 are correctly placed.
Tips/channels are
incorrectly positioned on
the elution slot during the
elution step. Ensure that the elution rack is placed on the elution slot in the correct orientation.
Ensure that the correct sample tubes are loaded, as defined in the run. Only use sample
tubes/racks that are compatible with the QIAsymphony SP/AS instruments. For a full list of
compatible sample tubes/racks, visit www.qiagen.com/goto/QIAsymphony.
If the error persists, contact QIAGEN Technical Services.