Direct plasma injection method for the analysis of tryptophan metabolites by high-performance liquid chromatography coupled with precolumn deproteinization

✍ Scribed by Ikue Morita; Tsutomu Masujima; Hisanobu Yoshida; Hideo Imai

• Publisher: Elsevier Science
• Year: 1985
• Tongue: English
• Weight: 524 KB
• Volume: 151
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(85)90188-5

✦ Synopsis

Reversed-phase HPLC method by direct plasma injection has been developed for the analysis of major tryptophan metabolites (both metabohtes in kynurenine pathways and in indole pathways). Two columns were used: one was a short precolumn of protein-coated octadecylsilane (ODS) for deproteinization and also for trapping of tryptophan metabolites, and the other was an analytical column ofthe usual ODS. By a column-switching method, the metabolites trapped in the precolumn were allowed to be eluted through the analytical column. The recovery of the spiked metabolites in plasma by the present method was almost quantitative (98-102%) with good reproducibility (CV less than 38, within-run), and the method is determined to be simple and reproducible for the analysis of total (free + protein-bound) tryptophan metabolites in plasma. The analysis of rabbit plasma showed several peaks corresponding to kynurenine, kynurenic acid, S-hydroxyindole-3-acetic acid, indole-3-lactic acid, indole-3-acetic acid, indole-3-propionic acid, and 5-hydroxytryptamine in addition to tryptophan. 0 1985 Academic pns$ hc.