Thiamine and TMP in serum/plasma
Thiamine (vitamin B1) is a water-soluble vitamin involved in energy metabolism and that is not stored in large amount in the body. The prevalence of deficiency is low (0.4 -2.8 %) in a Western general population, but increases markedly in alcoholics, in subjects with caloric restriction, prolonged nausea, parenteral nutrition, malabsorption (after bariatric surgery) or diabetes (3).
In serum/plasma, free thiamine accounts for about 85 % and TMP for about 15 %. Thiamine triphosphate and thiamine disphosphate (ThDP), the active co-enzyme form, are not detected in serum/plasma, but are the prevailing species in erythocytes and whole blood.
Plasma thiamine and TMP correlate positively with the established biomarker, erythrocyte ThDP, and all thiamine forms respond signiﬁcantly to thiamine intervention. Plasma thiamin is the biomarker most responsive to thiamin intake (2).
Performance of the assay (LC-MS/MS)
Lower limit of detection (LOD) (thiamine/TMP): <0.25/0.5 nmol/L.
Within-day CV: 4/8 %; between-day CV: 7/16 %.
Assessment of vitamin B1 status and recent intake.
Specimen, collection and processing
Matrix: EDTA plasma and serum.
Volume: Minimum volume is 60 µL, but 200 µL is optimal and allows reanalysis.
Preparation and stability:
Transportation; for general instruction on transportation, click here.
Frozen, on dry ice.
Reported values, interpretation
Reported values (thiamine/TMP): 2-50/2-15 nmol/L
Intraclass correlation coefficients (ICC): na.
1. Midttun, O., Hustad, S., and Ueland, P.M. (2009). Quantitative profiling of biomarkers related to B-vitamin status, tryptophan metabolism and inflammation in human plasma by liquid chromatography/tandem mass spectrometry. Rapid Commun Mass Sp 23, 1371-79.
2. McCann, A., Midttun, Ø., Whitfield, K.C., Kroeun, H., Borath, M., Sophonneary, P., Ueland, P.M., and Green, T.J. (2017). Comparable performance characteristics of plasma thiamine and erythrocyte thiamine diphosphate in response to thiamine fortiﬁcation in rural Cambodian women. Nutrients 9, 676.
3. Kerns, J.C., and Gutierrez, J.L. (2017). Thiamin. Adv Nutr 8, 395-397.