Validation of Workflow Changes, Phage Concentration and Reformatted Detection Threshold for the Sample6 DETECT/L™...

Area of Science:

• Food safety and microbiology
• Environmental surface testing
• Bacterial detection methods

Background:

• The AOAC Research Institute certified Sample6 DETECT/L for Listeria species detection on stainless steel surfaces in 2014.
• Modifications in 2016 enhanced reagents, phage concentration, sample volume, and compatibility with polyurethane sponges.

Purpose of the Study:

• To validate workflow changes in the DETECT/L assay to enhance sensitivity and ease-of-use.
• To ensure the modified assay continues to meet performance expectations.
• To optimize assay performance through changes in phage concentration, detection threshold, and inclusion of a confirmation step.

Main Methods:

• Inclusivity, exclusivity, and robustness testing were performed by Sample6.
• A third-party laboratory compared the modified DETECT/L assay with the USDA reference method.
• The study focused on stainless steel environmental surface matrices.

Main Results:

• Validated changes included adjusted phage concentration, detection threshold, and the addition of a DETECT Check confirmation step.
• The modified assay demonstrated enhanced accuracy and optimized performance.
• Comparative study results indicated the changes meet or exceed the performance of the current DETECT/L configuration.

Conclusions:

• The modifications to the Sample6 DETECT/L assay successfully enhanced its sensitivity, accuracy, and ease-of-use.
• The updated assay maintains or improves upon its established performance for Listeria species detection.
• The validated changes ensure the continued reliability of DETECT/L for environmental surface monitoring.