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12)Load capped tubes into a clean and decontaminated 3M Molecular
Detection Speed Loader Tray. Close and latch the 3M Molecular
Detection Speed Loader Tray and lid.
13)Review and confirm the configured run in the 3M Molecular Detection
Software.
14)Select the Start button in the software and select the instrument for
use. The selected instrument’s lid automatically opens.
15)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 60 minutes, although positives may be
detected sooner.
16)All samples must be confirmed from the enrichment broth for the
presence of
E. coli
O157 using appropriate approved reference
methods.
Method Comparison Study
This study included a method comparison evaluation of the 3M MDA 2 –
E. coli
O157:H7 compared to the USDA/FSIS-MLG 5.09
Detection, Isolation and Identification
of Escherichia coli O157:H7 from Meat Products and Carcass and Environmental
Sponges
for the detection of
E. coli
O157:H7 in raw ground beef (73% lean). The food
matrix, raw ground beef (72% lean 27% fat), was purchased from a local distributor,
prescreened for natural contamination of the target analyte and analyzed for total
aerobic count by the FDA/BAM Chapter 3 method [4]. Following the screening, raw
ground beef was inoculated with
E. coli
O157:H7
as indicated in Table A. The method
comparison study consisted of evaluating a total of 30 un-paired sample replicates for
the matrix. Within each sample set, there were 5 uninoculated samples (0 CFU/test
portion), 20 low level inoculated samples (0.2-2 CFU/test portion), and 5 high level
inoculated samples (2-5 CFU/test portion). All samples analyzed by the 3M MDA 2 -
E.
coli
O157, regardless of presumptive results, were culturally confirmed by the reference
method after10 hours of incubation.
Table A: Matrix and Inoculating Organism
Matrix/Test
Portion Size
Inoculating
Organism
Target Inoculum Level
# of
Replicates
Testing Time
Point/Incubation
Temperature
Reference
Method
(Enrichment)
Raw Ground
Beef 73% lean
(325 gram)
E. coli
O157:H7
ATCC
1
43895
0 CFU/ Test Portion
5
10 hours at
41.5°C
USDA/FSIS
MLG 5.09
(mTSB +
CAA)
0.2-2 CFU/ Test Portion
20
2-5 CFU/ Test Portion
5
1
ATCC - American Type Culture Collection