Rapid assay for γ-carboxyglutamic acid in urine and bone by precolumn derivatization and reversed-phase liquid chromatography

✍ Scribed by Yacoob Haroon

• Publisher: Elsevier Science
• Year: 1984
• Tongue: English
• Weight: 467 KB
• Volume: 140
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(84)90175-1

✦ Synopsis

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.