Matrix MicroScience has gained AOAC-RI approval for its new range of Pathatrix Pooling products for the testing of Salmonella and Listeria.

Pathatrix Pooling is unique in that it relies on "post-enrichment pooling" as opposed to conventional pre-enrichment sample pooling, the key point being that the Pathatrix pooling approach maintains 100% sample integrity and traceability. A number of significant benefits that the Pathatrix Pooling Strategy provides to all microbiological laboratories can be summarised:

• Increased sample throughput i.e. upto 5 times
  
• Substantial cost reduction i.e. >60%
  
• Significant labour savings i.e. >60%
  
• Compatible with a wide range of end point detection technologies
  
• Original sample integrity maintained 100%
  

The Pathatrix Pooling principle relies on the pooling of up to 5 x 50ml sub-samples to create a single 250ml composite sample, which can be analysed by a range of end point detection technologies. In this way negative samples can be screened out very efficiently and if a positive pooled sample is obtained then the original post enriched samples, where complete sample integrity has been maintained, can be very quickly re-analysed to achieve rapid results. In addition to routine analysis this can be a very effective tool for contamination incidents and/or positive release scenarios.

As the majority of companies find that 98% + of all routine food samples tested for pathogens are negative this new technique offers great opportunities for cost savings, increased laboratory efficiency and the ability to increase the number of samples tested with the current laboratory facilities. For example a Company who carries out approximately 100,000 analyses a year and is using a molecular detection method could save €400,000+ / annum by using the Pathatrix Pooling method.

The Salmonella & Listeria Pathatrix Pooling products are AOAC-RI approved for a variety of food types, including difficult sample matrices. The Pathatrix Pooling Kits offer a unique approach to pathogen testing for all food-testing laboratories.



The Pathatrix system requires less than two minutes hands-on time per test and utilises a proven technology, which can be adopted in any microbiology laboratory, with the minimum of retraining. Viable cultures are produced during the test allowing full and detailed analysis of any positive results.

Pathatrix is unique in that it is the only microbial detection system that can analyse the entire 225ml + 25g sample simultaneously by re-circulating the sample through a "capture phase" where the antibody coated magnetic beads are immobilised.

A standard 25g food sample is homogenised with 225ml of growth media in a stomacher. Pathatrix capture reagents, which consist of antibody coated magnetic particles specific to the target pathogen, are then added directly to the sample. The sample is loaded onto the Pathatrix workstation using a Matrix proprietary consumable pack, connecting the sample to the circulatory system in preparation for the Capture-Culture step.

Once loaded, the Pathatrix workstation is typically pre-programmed to run for 30 minutes at the desired incubation temperature. Upon completion of the run, the target microorganisms are bound onto the phase by the capture reagent. Residual debris and non-specific binding are removed during a single wash step.

The capture phase is disconnected from the system and the capture reagent/pathogen complexes are eluted by washing the phase into a vessel. The captured pathogen complexes are then concentrated into a small volume. The sample can be plated directly onto selective media and incubated overnight for visualization the following morning or be directly analysed by PCR for a very rapid result.

There are a variety of Pathatrix tests that enable results to be obtained within as little as 5hrs to 24hrs from point of sample to result.