Vitamin D

Synonyms: 25-hydroxyvitamin-D3 (25OH-D3), 25-hydroxycholecalciferol, calcifediol, calcidiol; 25-hydroxyvitamin-D2 (25OH-D2), 25-hydroxyergocalciferol.
Method(s): LC-MS/MS.
What is measured: 25-hydroxyvitamin-D3 and 25-hydroxyvitamin-D2.

What is measured on the same platform, click here.
Platform H: Vitamins A, D, E and K

Performance of the assay

Lower limit of detection (LOD) (25OH-D3/25OH-D2): 3.3/3.3 nmol/L.
Within-day CV: 4-5/4-5 %; between-day CV: 7-8/5-8 %.


Assessment of vitamin D status.

Specimen, collection and processing

Patient/subject: Vitamin D levels show a high level of seasonality due to the influence of sunlight.
Matrix: Serum or EDTA plasma.
Volume: Minimum volume is 50 µL, but 200 µL is optimal and allows reanalysis.
Preparation and stability: Samples should be put on ice, and protected from light.

Transportation; for general instruction on transportation, click here.

Frozen, on dry ice.

Reported values, interpretation

Reported values (25OH-D3/25OH-D2): 20-150/0-4 nmol/L.
Intraclass correlation coefficient (ICC) (25OH-D3/25OH-D2): 0.71/na.