AOAC 2019 First Action Methods

C.

General Instructions

(a)

The GENE-UP ® Listeria monocytogenes 2 (LMO 2) kit is for professional use only with the

GENE-UP ® Lysis kit. (b)

Comply with Good Laboratory Practices.

(c)

Do not use reagents after the expiration date indicated on the label.

(d)

Visually inspect vials before testing. Do not use vials with evidence of damage, leakage, or

deterioration. (e)

Do not mix reagents (or disposables) from different lots.

(f)

Powder-free latex or nitrile gloves are recommended for all PCR steps.

(g)

The equipment and accessories should be regularly cleaned and decontaminated.

(h)

Never remove the caps from the lysis tubes.

(i)

Do not try to remove the strip tube caps once they have been sealed to the PCR strip tubes

(j) Spills should be wiped up thoroughly after treatment with bleach or a nucleic acid degradation solution. See the GENE-UP ® user manual for information on cleaning spills on or in the instrument. Do not autoclave solutions containing bleach. D. Sample Enrichment [Allow the enrichment broths to reach 15–25°C before use. For select matrices, pre-warm LPT broth to 35 ± 1°C prior to use. Frozen samples should be thawed before analysis. Use a blender bag containing filter.] (a) Deli ham, deli roast beef, deli turkey, turkey hot dogs, fresh spinach, mixed bagged salad, cooked shrimp, smoked salmon, vanilla ice cream, Mexican soft cheese, pork rillettes, raw milk, salmon offcuts, mixed precooked vegetables, mixed salad and process water (25 g). ― Add 225 mL LPT broth. Homogenize and incubate at 35 or 37 ± 1°C for 22–26 h. (b) Whole liquid eggs (100 mL). ― Add 900 mL of pre-warmed LPT broth. Homogenize and incubate at 35 ± 1°C for 22–26 h. (c) Deli ham and Mexican soft cheese (125 g). ― Add 375 mL of LPT broth. Homogenize and incubate at 35 ± 1°C for 24–28 h. (d) Whey powder (375 g). ― Add 1125 mL of pre-warmed LPT broth. Homogenize and incubate at 35 ± 1°C for 24–28 h. (e) Environmental samples. ― Add enough LPT broth to cover the sampling device (ex. 10 mL for a swab and 100 mL for a sponge). Homogenize and incubate at 35 or 37 ± 1°C for 22–26 h.