Listeria assay system

Neogen Corporation has received a matrix extension for its Performance Tested Method Certification (PTM #101202) from the AOAC Research Institute for its ANSR for Listeria assay. In addition to the original claims, the following matrices are now included in the approval: pasteurised milk, Mexican-style cheese, ice-cream, smoked salmon, lettuce, rockmelon, guacamole and pasteurised liquid egg.

The original AOAC-RI approval covered the use of the ANSR system to detect Listeria in environmental matrices that included sponge or swab samples from stainless steel, plastic, ceramic tile, sealed concrete and rubber environmental surfaces.

The ANSR system, available to detect Salmonella or Listeria, uses an isothermal DNA amplification process to amplify DNA to detectable levels and fluorescent molecular beacon technology for detection of the pathogen target. Combined with ANSR’s single enrichment step, Neogen’s pathogen detection method can provide DNA-definitive results for Listeria in as few as 16 h from the time the sample is taken, the company says.

Unlike PCR-based methods, ANSR requires only a single reaction temperature, which eliminates the time-consuming heating and cooling cycles of older methods. The ANSR system’s small benchtop footprint and simple test procedure make it an easy fit in laboratory workflows. Incorporating an internal control for each assay, ANSR results are DNA definitive as well as rapid.