title: Rapid assay for gamma-carboxyglutamic acid in urine and bone by precolumn derivatization and reversed-phase liquid chromatography.
abstract: A reversed-phase high-performance liquid chromatographic assay for the analysis of gamma-carboxyglutamic acid (Gla) in urine and bone protein hydrolyzates is described. The method employs precolumn derivatization with o-phthalaldehyde and mercaptoethanol. Gla was quantified by reference to an internal standard (beta-carboxyaspartic acid). The "within-run" coefficient of variation of the assay for Gla in urine was between 2.1 and 3.4%, and that for bone protein hydrolyzates was 3.2%. The "between-run" coefficient of variation ranged from 4.1 to 5.5%. There was good agreement between the measurement of urinary Gla by high-performance liquid chromatography and amino acid analyzer. Free Gla could not be detected in serum.
mesh_terms: D015055:1-Carboxyglutamic Acid / Q000032:analysis* / Q000097:blood / Q000652:urine; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D001842:Bone and Bones / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D005971:Glutamates / Q000032:analysis*; D008623:Mercaptoethanol; D051381:Rats; D009764:o-Phthalaldehyde
chemical_list: D000596:Amino Acids; D005971:Glutamates; D015055:1-Carboxyglutamic Acid; D008623:Mercaptoethanol; D009764:o-Phthalaldehyde