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Table 6, Tab 11, shows the Abbott SLV results for choline compared to the Thermo Fisher ion
chromatography method (this first action method is currently being tested for Reproducibility in an MLT
Study), AOAC 999.14 (the legacy colorimetric method, with enzyme treatment, conducted on our behalf
by Covance Labs, 2 days in duplicate means), and the legacy Abbott method that employs an
immobilized enzyme reactor (IMER) to convert choline to betaine and peroxide. The latter method
detects the concentration of peroxide with electrochemical detection, which is proportional to the
choline concentration in the sample.
Table 7a-d, Tab 12, shows the 6 x 2 means for each matrix as a function of instrument for choline and
carnitine, and the overall 6x2x2 means across both instruments. It also compares the free vs. total
concentrations.
The final tab, Tab 13, lists the previous ERP comments and how they were handled for this SLV.
Following is a more detailed summary of method equipment and procedures.
Candidates for 2016 Method of the Year
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