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The candidate presumptive and confirmatory results were compared by determining the difference
1
between the POD values for each matrix and concentration (dPOD
CP
= POD
CP
- POD
CC
). If the confidence
2
interval of a dPOD does not contain zero, then the difference is statistically significant at the 5% level.
3
The candidate and reference method results were compared by determining the difference in POD
4
values between the candidate and reference methods for each matrix and concentration (dPOD
C
= POD
C
5
- POD
R
). If the confidence interval of a dPOD does not contain zero, then the difference is statistically
6
significant at the 5% level.
7
AOAC Official Method ####
8
DuPont™ BAX® System Real-Time PCR Assay for
Salmonella
- Method for Detection of
Salmonella
in
9
Foods and Selected Environmental Surfaces
10
(Applicable to the detection of
Salmonella
in raw ground beef*, ground beef with soy, beef trim,
11
frankfurters, shrimp, ground turkey, chicken wings, poultry rinse*, dried eggs, shell eggs, fresh bagged
12
lettuce*, frozen peas, orange juice, cream cheese*, nonfat dry milk, ice cream, peanut butter, cocoa,
13
white pepper, infant formula, and dry pet food*, and on stainless steel*, ceramic tile, and plastic
14
surfaces)
15
* Previously validated as Performance Tested Method
SM
#081201
16
Safety Precautions
17
Kits – The reagents used in the BAX® System should pose no hazards when used as directed. Dispose of
18
lysate, PCR mixture and other waste according to your site practices.
19
Cycler/detector – Only qualified laboratory personnel should operate the cycler/detector. Do not
20
attempt to repair the instrument. Live power may still be available inside the unit even when a fuse has
21
blown or been removed. Refer to the BAX® System User Guide for maintenance procedures when
22
cleaning the unit or changing a fuse. The heating block can become hot enough during normal operation
23
to cause burns or cause liquids to boil. Wear safety glasses or other eye protection at all times during
24
operation.
25
Enrichment Broths – All enrichment broths may contain varying pathogens whether they contain
26
Salmonella
or not and thus should be sterilized and disposed of using proper procedures following any
27
culture-based confirmatory steps.
28
A.
Principle
29
The BAX® System uses the Polymerase Chain Reaction (PCR) to amplify a specific fragment of bacterial
30
DNA, which is stable and unaffected by growth environment. The fragment is a genetic sequence that is
31
unique to the genus
Salmonella
, thus providing a highly reliable indicator that the organism is present.
32
The BAX® System simplifies the PCR process by combining the requisite primers, polymerase and
33
nucleotides into a stable, dry, manufactured tablet already packaged inside the PCR tubes. After
34
amplification, these tubes remain sealed for the detection phase, thus significantly reducing the
35
potential for contamination with one or more molecules of amplified PCR product.
36
Dupont BAX Salmonella Pre- Collaborative Study
For Expert Review Panel Use Only
Do Not Distribute
AOAC INTERNATIONAL