AOAC RI ERP Final Action Recommendations eBook

Dupont BAX Salmonella PTM Report Modification Approved 2012 / PTM Certification No. 081201 For Expert Review Panel Use Only Do Not Distribute

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14. METHOD COMPARISON RESULTS

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The results of the method comparison studies are summarized in Tables 2 and 3 below. For

all sample types and enrichment methods tested, the updated BAX® System method

returned results that were identical to the certified method. POD analysis demonstrates no

statistically significant difference between results of the updated BAX® System method and

the reference culture methods.

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Fluorescent Probe Performance

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Performance of the fluorescent probes in the additional eight cycles do not appear to suffer

either by photo bleaching, which would lead to decreased signal for a positive reaction, or by

quencher degradation, which would lead to a false positive rise in signal. Thousands of reactions

have been run internally to date in the algorithm training and validation phases of the modified

protocol. Examples of typical reactions are shown below in Figure 1 (negative reactions) and

Figure 2 (positive reactions). Data in these figures is typical of data obtained during algorithm

training. Additional data is available upon request.

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