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“DERIVATIZATION” ANALYSIS METHOD
Proprietaryand confidential — do not distribute
© 2015 Abbott Laboratories
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SAMPLE PREPARATION
•
Samples are prepared by dilution in water followed by protein precipitation with
acetonitrile.
•
An aliquot of the sample extract is derivatized with 2 nitro phenylhydrazide (2
-
-
-
NPH) in the presence of 1-ethyl-3-(-3-dimethylaminopropyl) carbodiimide
hydrochloride (EDC).
•
This reaction achieves the coupling of the carboxyl group of monofluoroacetate to
the amino group of 2-NPH with the formation of an amide bond.
•
Samples are processed through a solid-phase extraction step in order to exchange
sample solvent and achieve a 5-fold concentration of the extract.
Proprietaryand confidential — do not distribute
© 2015 Abbott Laboratories
•
A stable-isotope labeled internal standard is incorporated into the sample
preparation to correct for instrument response and losses in sample preparation.
•
Overall sample dilution of 1:10
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