title: Measurements of sub-nanomolar concentrations of unmetabolised folic acid in serum.
abstract: We describe a combined HPLC/microbiological assay procedure for the sub-nanomolar analysis of unmetabolised folic acid (pteroylglutamate) in human serum. This metabolically unaltered form of the vitamin arises following the consumption of folic acid either in supplemental form or in fortified foods. Following HPLC separation of folic acid from other folate derivatives the folic acid fraction was concentrated by C(18) Sep-Pak cartridges and assayed by Lactobacillus casei microbiological assay. The present assay allows the quantitation and kinetic analysis of the effects of consumption of folic acid.
authors.affiliation: Department of Clinical Medicine, University of Dublin, Trinity College, Ireland.
authors.forename: Mary Rose
authors.initials: MR
authors.lastname: Sweeney
authors.forename: Joseph
authors.initials: J
authors.lastname: McPartlin
authors.forename: Donald George
authors.initials: DG
authors.lastname: Weir
authors.forename: John Martin
authors.initials: JM
authors.lastname: Scott
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005492:Folic Acid / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D005492:Folic Acid