Update, April 30, 2025: Vitamin Tissue Assays Available
We previously announced changes to several vitamin assays. See below for details. We are happy to announce two more assays have been transitioned to the new method and are no longer unavailable.
- Vitamin E, Tissue (50211)
- Vitamin A, Tissue (50207)
UPDATE, April 22, 2025:
Due to reagent unavailability, changes to several vitamin assays planned to go into effect on May 13, 2025 have been completed ahead of schedule and will go into effect on April 23, 2025. Additionally, some assays will be temporarily unavailable until they can be transitioned to a new method. The details outlined below have been updated accordingly.
April 15, 2025: Several vitamin assays will change effective April 23, 2025 (not May 13, 2025 as originally planned). Please read on for more information on changes to Vitamin A, Serum; Vitamin E, Serum and CSF; Vitamin Profile; Beta-Carotene, Serum; and Vitamin E: Cholesterol Ratio for Bovine Serum.
New Method for Vitamins A and E, Vitamin Profile
Effective April 23, 2025, the MSU VDL has transitioned measurement of vitamins A and E to a new method. Historically, we have utilized UPLC with photodiode array (PDA) for vitamin analysis. Moving forward, we are shifting to UPLC tandem mass spectrometry, better known as LC-MS/MS. This change affects the following assays:
- Vitamin A (retinol), Serum (50208)
- Vitamin E, Serum (50212)
- Vitamin E, CSF (50256)
- Vitamin Profile (50229)
Clients will notice a subtle shift in reference intervals for Vitamins A and E due to the increased sensitivity and specificity of the LC-MS/MS instrument used. Prices for these vitamin A and E assays will remain the same.
Some Assays Temporarily Unavailable
Additional assays must be transitioned to a new method utilizing different reagents. The assays listed below are temporarily unavailable beginning April 23, 2025:
- Vitamin E, Tissue (50211) - available as of April 30, 2025
- Vitamin E, Feed (50210)
- Vitamin E, Other (50213)
- Vitamin A, Tissue (50207) - available as of April 30, 2025
- Vitamin A, Feed (50206)
- Vitamin A, Other (50209)
- Beta-Carotene, Feed (50216)
- Beta Carotene, Other (50215)
We will provide updates when these changes occur and the assays are available.
Discontinuing Measurement of Beta-Carotene in Serum
Because of the limited clinical utility of beta-carotene in serum, that assay (50217) is no longer available as a stand-alone and will not be included in the serum vitamin profile (50229) effective April 23, 2025. The price for the vitamin profile will be adjusted to reflect this change.
Discontinuing Measurement of Vitamin E: Cholesterol Ratio in Bovine Serum
As part of the transition to a new method for measuring vitamin E in serum effective April 23, 2025, we will no longer measure cholesterol in bovine samples submitted for Vitamin E, Serum (50212) or the Vitamin Profile (50229). This change will reduce turn-around times.
Cholesterol (10391) can be ordered separately when clinically relevant.
Why are we making this change?
Historically, the MSU VDL provided bovine serum vitamin E concentrations in the context of cholesterol concentrations as a ratio. Cholesterol is a relative indicator of serum lipoprotein concentrations which do influence vitamin E status particularly at varying stages of lactation. However, recent research has concluded that while the adjustment of vitamin E to cholesterol increases accuracy of assessment, it does not enhance its biomarker function with respect to prediction of disease.
Page last updated: April 30, 2025
Page published: April 15, 2025