title: Insolubilized pure human intrinsic factor used for quantitation of cobalamins in serum.
abstract: The use of insolubilized pure human intrinsic factor as binding protein in an isotope dilution assay for quantitation of serum cobalamins is described. The reference interval was 200-600 pmol/l. The coefficients of variation were 0.05 to 0.13 and the equilibrium constant for association to cyanocobalamin was 2 x 10(11) 1/mol. The major advantage of the presented method is that intrinsic factor is kept saturated with cobalamin and is thereby stable until just prior to use.
mesh_terms: D003037:Cobalt Radioisotopes; D006801:Humans; D007437:Intrinsic Factor; D007700:Kinetics; D011865:Radioisotope Dilution Technique; D014805:Vitamin B 12 / Q000097:blood*
chemical_list: D003037:Cobalt Radioisotopes; D007437:Intrinsic Factor; D014805:Vitamin B 12