Chapter III. The BAX® System X5 PCR Assays
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BAX® System X5 User Guide
Using Analog Heating and Cooling Blocks with the BAX®
System Assays
If you do not wish to use the Automated Thermal Block for automated sample lysis, the lysis steps for the BAX®
System method may also be performed using separate analog heating and cooling blocks. Follow the instructions
below to perform sample lysis using separate analog heating and cooling blocks.
1. Follow the protocols listed
under “Enrich Samples” to combine samples with the appropriate enrichment
media and incubate them at the appropriate temperature and duration.
2. Turn on the two analog heating blocks and set them to the appropriate temperatures for your target:
BAX® System X5 Assay
Set Heating Blocks To
E. coli
O157:H7
Salmonella
37°C and 95°C
Genus
Listeria
L. monocytogenes
55°C and 95°C
3. Make sure that the two cooling blocks have been refrigerated overnight or otherwise chilled at 2-8°C.
4. Follow the instructions above to prepare BAX® System lysis reagent.
5. Transfer
200 μL lysis reagent to each of the cluster tubes.
6. Transfer 5
μL* enriched sample to the corresponding cluster tubes, using new pipette tips for each sample.
*
For E. coli O157:H7, transfer 20 μL enriched sample if using BAX® System MP media for enrichment
7. Place cluster tubes into the heating blocks for the appropriate time as described in the table below:
BAX® System X5 Assay
Heating Step #1
Heating Step #2
Cooling Step
E. coli
O157:H7
Salmonella
Place rack of cluster tubes
on the heating block pre-
warmed to 37°C for 20
minutes
Transfer cluster tubes
to heating block pre-
warmed to 95°C for 10
minutes
Place the cluster tubes
into a chilled (2-8°C)
cooling block for at least 5
minutes
Genus
Listeria
L. monocytogenes
Place rack of cluster tubes
on the heating block pre-
warmed to 55°C for 30
minutes
8. Follow the instructions above to hydrate PCR tablets.
9. Follow the instructions above to complete a BAX® System process run.
