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FOR EXPERT REVIEW PANEL USE ONLY
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1
Expert Review Panel for Infant Formula and Adult Nutrition
Evaluation of Method: VitD-17
#2
Title: Determination of Vitamin D in Milk Products by UPLC-MS-MS with 4-Phenyl-1,2,4-triazoline-3,5-
dione (PTAD) Derivatization
Author:
CDC_SH
Summary of Method:
Test samples are saponified, extracted, and the solvent evaporated. Vitamin D is derivatized with PTAD, 4-
phenyl-1,2,4-triazoline-3,5-dione, and then determined by UHPLC-MS/MS.
Method Scope/Applicability:
Determination of total vitamin D2 and vitamin D3 in all forms (powders, ready-to-feed liquids, and liquid
concentrates) of infant, adult, and pediatric nutritional formulas.
Questionable on previtamin D determination.
General comments about the method:
This method is a well written method, it is easy to understand. The derivatization procedure is simple.
Stable isotope labeled vitamin D3 was used as an internal standard. The detection is sensitive and selective.
Some of the difference between the two method:
The chromatography is within 10 min. The saponification is conducted at low temperature overnight. The
derivatization reaction time is 30 min. After saponification, the hexane extract is dried before the PTAD
reaction. NIST SRM 1849a and three powder samples and one liquid samples were used in recovery study.
Method Clarity:
The method was easy to follow. However, there is no info on how the results were calculated in the
method.
Method Safety Concerns:
No particular safety concerns.
Pros/Strengths:
Use of stable isotope labeled Vitamin D2 as internal standard.
PTAD derivatization improves the method sensitivity and selectivity.
Cons/Weaknesses
Need to have a purity check on standards
Question about the previtamin determination.
VitD-17 Review Forms