Enantioselective high-performance liquid chromatography assay of (+)R- and (−)S-α-lipoic acid in human plasma

✍ Scribed by G. Niebch; B. Büchele; J. Blome; S. Grieb; G. Brandt; P. Kampa; H. H. Raffel; M. Locher; H. O. Borbe; I. Nubert; I. Fleischhauer

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 224 KB
• Volume: 9
• Category: Article
• ISSN: 0899-0042
• DOI: 10.1002/(sici)1520-636x(1997)9:1<32::aid-chir7>3.0.co;2-i

✦ Synopsis

A specific plasma level assay for the enantiomers of alpha-lipoic acid is described. It makes use of liquid-liquid extraction, chemical reduction to the dithiol enantiomers, and their precolumn chiral derivatisation with o-phthalaldehyde in the presence of D-phenylalanine. The two diastereomeric derivatives are separated by reversed-phase HPLC with fluorescence detection. The working range of the assay is between 15 ng/ml (lower limit of quantitation) and 1,000 ng/ml for either enantiomer.