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IMPROVEMENTS MADE TO DERIVATIZATION
PROCEDURE
•
A protein precipitation step with acetonitrile was included.
•
Reagents were prepared according to Miwa et al. (2000), J. Chrom. A
881 365 which reduces the number of steps involved in the
,
,
derivatization process. Ibid. for reaction conditions (80 °C, 5 min)
which reduces overall sample processing time.
•
Excess reagent was not removed. There was no indication that the
presence of excess reagent had any adverse effect on the analysis or
the instrumentation.
•
One single reversed phase SPE step was used for solvent exchange
and 5-fold concentration of extract.
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© 2015 Abbott Laboratories
•
Tandem mass spectrometry (MS/MS) was used which adds another
level of selectivity compared to single stage MS.
•
Stable isotope labeled internal standard was used for accurate
quantitation.
March17,2015
MFA‐AOAC, 2015
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29
CONCLUSIONS
Direct Analysis Method
•
A simple and high throughput LC-MS method has been developed for nutritional
products analysis of MFA
•
Specificity and quantitation in matrix demonstrated
•
30 ppb quantitation limit in powders
•
Implemented for routine analysis at a third part laboratory for samples analysis
Derivatization Method
•
A streamlined derivatization method has been developed for nutritional
products analysis of MFA
Proprietaryand confidential — do not distribute
© 2015 Abbott Laboratories
•
Specificity and quantitation in matrix demonstrated
•
10 ppb quantitation limit in powders
•
Confirmatory method
March17,2015
MFA‐AOAC, 2015
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30