ERP Micro December 2019

infirmed (2). The disease can also be transmitted between humans, notably from pregnant women to the fetus (3). The seriousness of the disease dictates the need for highly reliable and sensitive methods for the detection of the pathogen. The GENE-UP ® Listeria monocytogenes 2 (LMO 2), a real-time PCR technology, utilizes dual Fluorescence Resonance Energy Transfer (FRET) hybridization probes to detect L. monocytogenes in a variety of foods and environmental samples. The resulting fluorescent signal from the FRET interaction, which forms a real-time amplification curve, is how the amplified target is detected by the GENE-UP ® Thermocycler. The assay can detect L. monocytogenes following 22 h of enrichment for most food products and environmental samples. Prior to the collaborative study, the GENE-UP ® method was validated as part of the AFNOR NF Validation certification process. The assay was evaluated for a broad range of categories, including meat products; dairy products; seafood products; vegetable products; composite foods and production environmental samples. All AFNOR method comparison studies (MCS) were conducted independently by an Expert Laboratory, Institut Scientifique d’Hygiène & d’Analyse (ISHA; Massy, France). For the MCS evaluation, the candidate method was compared to the ISO 11290-1:1996/Amd.1:2004 Microbiology of food and animal feeding stuffs — Horizontal method for the detection and enumeration of Listeria monocytogenes — Part 1: Detection method AMENDMENT 1: Modification of the isolation media and the haemolysis test, and inclusion of precision data reference method (4). MCS studies included an inclusivity and exclusivity evaluation, a sensitivity study and a relative limit of detection (RLOD) study. During the sensitivity study, 551 different food items (from the 6 categories) were evaluated by the candidate and reference method. Seven food items (pork rillettes, raw milk, salmon offcuts, mixed precooked vegetables, mixed salad, environmental surface swabs and process water) were evaluated during the RLOD study, which can be considered equivalent to the matrix studies conducting during an AOAC ® Performance Tested Methods SM (PTM) evaluation. All studies

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