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FOR EXPERT REVIEW PANEL USE ONLY
NOT FOR DISTRIBUTION
1
Expert Review Panel for Infant Formula and Adult Nutrition
Evaluation of Method:
Chol-08/Carn-07
This method is currently AOAC First Action for Carnitine (2015.10)
Title:
Determination of Free and Total Choline and Carnitine in Infant Formula and Adult/Pediatric Nutritional
Formula by Liquid Chromatography/Tandem Mass Spectrometry (LC/MS/MS)
Author:
Covance
Summary of Method:
The total method involves extraction of choline and carnitine using acid assisted microwave hydrolysis with
nitric acid, followed by filtration, addition of acetonitrile, and injection. The separation utilizes strong cation
exchange (SCX) with electrospray ionization (ESI) in positive mode.
Method Scope/Applicability:
Infant Formula and Adult/Pediatric Formulas
General comments about the method:
The acid-digestion method will under-recover phosphocholine, so it may not meet the SMPR. However, a
similar issue ie under-recovering carnitine esters due to absence of alkaline digestion did not prevent the
method becoming First Action for carnitine.
Method Clarity:
Clear directions for operation of the method, instruments. Clear equations describing how the standards
and samples are quantitated is required.
Method Safety Concerns:
None, beyond standard laboratory safety
Pros/Strengths:
Modern technique with simple straight forward analysis.
Cons/Weaknesses
Supporting Data
SPIFAN Kit used.
Performance Characteristics:
Results reported refers to Total Choline
#3
Chol-08 Review Forms