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FOR EXPERT REVIEW PANEL USE ONLY
NOT FOR DISTRIBUTION
4
The method leverages the specificity afforded by PTAD adduct derivatization to improve method
sensitivity and selectivity in the determination of vitamin D in Infant and Adult nutritional product
matrices. We have observed these challenges in previously reviewed methods where other,
similar compounds, can and do challenge chromatographic integrity even with MS/MS detection.
The use of LC-MS/MS with MRM also affords the use of multiple ion transitions for analyte
identification and quantitation. Stable-isotope internal standardization, especially as applied in
this method where the standards for both D
3
and D
2
are added prior to sample saponification, also
adds significantly to method robustness.
If there is a weakness in the data evaluated from this method, both in SLV and MLT, it is in the
limited vitamin D
2
data available. This is due to limited availability of vitamin D
2
fortified products.
As such, the method has not been as thoroughly evaluated for D
2
as for vitamin D
3
. Nonetheless,
the vitamin method performance metrics produced for vitamin D
2
data are similar to those
produced for vitamin D
3
and meet SMPR parameters.
Based on the data produced in this MLT, I can recommend this method for Final Action Status.