Total Collaborative Study Protocol_Solus One Salmonella v1 1

Method Developer Studies 

Product Consistency (lot‐to‐lot) and Stability Studies 

This study was carried out with pure cultures and examined three lots of Solus One  Salmonella kits 

for lot‐to‐lot consistency and product stability. Lots were chosen that were near their expiration date, 

near the middle of the expiration period, and recently manufactured. Data demonstrating no statistical 

difference in detection between lots and no significant time slope were required. 

For the product consistency (lot‐to‐lot) and stability study evaluation of Solus One  Salmonella , a 

Salmonella Typhimurium NCTC 5711 strain was cultured in non‐selective BHI broth for 20 ± 2 h at 37 ± 

1°C.  

The starter culture was diluted to approximately 10 1  CFU/mL in sterile BHI broth and used to 

inoculate ten–100 mL bottles of supplemented BPW Medium, which were subsequently incubated for 

20–22 h at 41.5 ± 1°C. After incubation, the culture samples were diluted with sterile supplemented 

BPW enrichment media to the LOD 50

of the method to obtain fractional detection levels.  

In addition, a non‐target strain Citrobacter freundii NCTC 6272 strain was cultured in BHI broth for 

20 ± 2 h at 37 ± 1°C. The starter culture was diluted to approximately 10 6 –10 7  CFU/mL in sterile BHI 

broth and used to inoculate ten–100mL bottles of BHI broth, which were subsequently incubated for 24 

h at 37 ± 1°C. Samples were used without dilution. 

Each lot of test kits were analyzed by the Solus One  Salmonella automated preparation method, 

with ten replicates of each of the undiluted and diluted  S. Typhimurium cultures, and ten replicates of 

the undiluted C. freundii  in a randomized blind coded fashion. 

Comparison of Solus One  Salmonella  test kit lots that were at their expiration date, near the middle

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