title: Resolution and binding site determination of D,L-thyronine by high-performance liquid chromatography using immobilized albumin as chiral stationary phase. Determination of the optical purity of thyroxine in tablets.
abstract: Human and bovine serum albumin bound to silica or aminopropyl silica were used as chiral stationary phases (CSPs). D,L-Thyronine, D,L-tryptophan, N-benzoyl-D,L-phenylalanine, D,L-warfarin and D,L-benzoin could be resolved on these CSPs using a mobile phase of 0.05 M phosphate buffer, pH 7.0. The capacity factor of D-thyronine was higher than that of L-thyronine. The resolution of D,L-thyronine was completely lost by the presence of bilirubin in the mobile phase, but only little affected by caprylate. By contrast, the resolution of D,L-tryptophan was not affected by bilirubin, but lost by the presence of caprylate. These results are consistent with binding of D-thyronine to the bilirubin binding site and L-tryptophan to the caprylate binding site in albumin, respectively, and suggests that such "displacement chromatography" can be used for the determination of binding sites. The optical purity of D-thyroxine in tablets was determined indirectly after de-iodination by catalytic hydrogenation.
authors.affiliation: Department of Chemistry BC, Royal Danish School of Pharmacy, Copenhagen.
authors.forename: L
authors.initials: L
authors.lastname: Dalgaard
authors.forename: J J
authors.initials: JJ
authors.lastname: Hansen
authors.forename: J L
authors.initials: JL
authors.lastname: Pedersen
mesh_terms: D000594:Amino Acid Oxidoreductases; D000818:Animals; D001665:Binding Sites; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D006868:Hydrolysis; D050830:L-Amino Acid Oxidase; D012709:Serum Albumin; D012710:Serum Albumin, Bovine; D012996:Solutions; D013237:Stereoisomerism; D013607:Tablets; D013970:Thyronines / Q000032:analysis* / Q000378:metabolism; D013974:Thyroxine / Q000032:analysis*
chemical_list: D012709:Serum Albumin; D012996:Solutions; D013607:Tablets; D013970:Thyronines; D012710:Serum Albumin, Bovine; D000594:Amino Acid Oxidoreductases; D050830:L-Amino Acid Oxidase; D013974:Thyroxine