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VIDAS LMX & LPT Collaborative Study
April 19, 2013
OMA-2013-Apr-XXX
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5.5
Apparatus
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5.5.1
Pipette with disposable tip – to dispense 250 μL.
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5.5.2
VIDAS Heat and Go
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5.5.3
Stomacher® bags with filters – for sample homogenization and
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enrichment
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5.5.4
Stomacher® 400 or equivalent – for sample homogenization.
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5.5.5
Incubators capable of maintaining 30±1°C, 37±1°C.
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5.6
Determination
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5.6.1
Enrichment
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5.6.1.1
Soft Mexican Cheese (25g)
- aseptically add the 25g test portion
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to 225 mL supplemented LMX broth prewarmed to 18-25°C.
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5.6.1.1.1
Mix in a Stomacher® bag with filter for 2 min.
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5.6.1.1.2
Incubate 26-30 hr at 37 ± 1°C.
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5.6.1.2
Soft Mexican Cheese (125g)
- aseptically add the 125g test
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portion to 375 mL LPT broth. Incubate 24-30 hr at 30 ± 1°
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prewarmed at 18-25°C.
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5.6.1.2.1
Mix in a Stomacher® bag with filter for 2 min.
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5.6.1.2.2
Incubate 24-30 hr at 30 ± 1°.
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5.6.1.2.3
Transfer 1 mL primary enrichment into 10 mL LPT
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broth. Incubate 22-26 hr at 30 ± 1°.
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5.6.2
Detection
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5.6.2.1
25g:
After incubation, transfer 0.25 mL of the enriched sample into
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an LMX strip. Place strip onto the VIDAS Heat and Go for 5 ± 1
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min. Cool the strip for 10 min and perform the VIDAS assay.
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5.6.2.2
125g:
After incubation, transfer 0.25 mL of enriched sample into
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an LMX strip and perform VIDAS assay. NO HEATING
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5.6.2.3 Store the enriched test portion at 2-8°C in case confirmation is
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required.
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5.7
Analysis
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5.7.1
For complete instructions, see the VIDAS or Mini VIDAS Operator’s
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Manual.
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5.7.2
Enter factory master calibration curve data into the instrument using the
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master lot entry (MLE) card.
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5.7.3
Remove the kit reagents and materials from refrigerated storage and allow
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them to come to room temperature for at least 30 min.
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5.7.4
Use one VIDAS LMX Reagent Strip and one VIDAS LMX SPR for each
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sample, control or standard to be tested. Reseal the storage pouch after
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removing the required number of SPRs.
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5.7.5
Enter the test code by typing or selecting “LMX” on the instrument. If the
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standard is to be tested, identify the standard by “S1” and test in duplicate.
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If the positive control is to be tested, identify it by “C1.” If the negative
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DRAFT DOCUMENT
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