3M Molecular Detection Assay 2 Manuel D'instructions page 11

8. Click the Start button in the software and select instrument for use. The selected instrument's lid automatically opens.
9. Place the 3M Molecular Detection Speed Loader Tray into the 3M Molecular Detection Instrument and close the lid to
start the assay. Results are provided within 75 minutes, although positives may be detected sooner.
10. After the assay is complete, remove the 3M Molecular Detection Speed Loader Tray from the 3M Molecular Detection
Instrument and dispose of the tubes by soaking in a 1-5% (v:v in water) household bleach solution for 1 hour and away
from the assay preparation area.
Notice: To minimize the risk of false positives due to cross-contamination, never open reagent tubes containing amplified
DNA. This includes Reagent Control, Reagent, and Matrix Control tubes. Always dispose of sealed reagent tubes by
soaking in a 1-5% (v:v in water) household bleach solution for 1 hour and away from the assay preparation area.
Results and Interpretation
An algorithm interprets the light output curve resulting from the detection of the nucleic acid amplification. Results are
analyzed automatically by the software and are color-coded based on the result. A Positive or Negative result is determined
by analysis of a number of unique curve parameters. Presumptive positive results are reported in real-time while Negative
and Inspect results will be displayed after the run is completed.
Presumptive positive samples should be confirmed as per the laboratory standard operating procedures or by following
the appropriate reference method confirmation
enrichment broth (if applicable), followed by subsequent plating and confirmation of isolates using appropriate
biochemical and serological methods.
In the context of the NF VALIDATION, all samples identified as positive by the 3M Molecular Detection Assay 2 - Listeria
must be confirmed by one of the following tests:
Option 1: Using the ISO 11290-1
Option 2: Implementing a confirmation method consisting of the following: Transfer 0.1 mL of the Demi-Fraser broth.
Streak directly onto selective agar described in ISO 11290-1
Option 3: Using nucleic acid probes as described in EN ISO 7218
selective agar (see Options 1 or 2).
Option 4: Using any other method certified NF VALIDATION, the principle of which must be different from 3M Molecular
Detection Assay 2 - Listeria. The complete protocol described for this second validated method must be used. All steps
prior to the start of confirmation must be common to both methods.
In the event of discordant results (presumptive positive with the alternative method, non-confirmed by one of the means
described above) the laboratory must follow the necessary steps to ensure the validity of the result obtained.
Note: Even a negative sample will not give a zero reading as the system and 3M Molecular Detection Assay 2 - Listeria
amplification reagents have a "background" relative light unit (RLU) reading.
In the rare event of any unusual light output, the algorithm labels this as "Inspect." 3M recommends the user to repeat
the assay for any Inspect samples. If the result continues to be Inspect, proceed to confirmation test using your preferred
method or as specified by local regulations.
If you have questions about specific applications or procedures, please visit our website at www.3M.com/foodsafety or
contact your local 3M representative or distributor.
, beginning with transfer from the primary enrichment to secondary
(1, 2, 3)
standard starting from Demi-Fraser enrichment
(3)
.
(3)
standard, performed on isolated colonies, from
(5)
11
EN (English)