Enrichment and high-performance liquid chromatography analysis of tryptophan metabolites in plasma

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

• Publisher: Elsevier Science
• Year: 1981
• Tongue: English
• Weight: 448 KB
• Volume: 118
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(81)90170-6

✦ Synopsis

Tryptophan metabolites with an indole ring are enriched by adsorption either as an ion pair with a trichloroacetic acid anion or as its undissociated form on porous polystyrene polymer (TSK 2000 S) from strongly acidic piasma deproteinized by trichloroacetic acid, and after washing with water, they are efuted with a 90% methanol solution. Following the removal of the solvent, the residue is dissolved in a small amount of water and then subjected to highperformance liquid chromatography (hplc) analysis. Using 0.2 ml of adsorbent, the recovery of the 500 pmol added for each of the tryptophan metabolites into 1.5 ml of deproteinized plasma is above 70%. This method is used for the analysis of normal rabbit and rat plasma. The hplc analysis, with native fluorescence detection, shows several peaks corresponding to tryptophan, $hydroxytryptophan, serotonin, 5-hydroxyindole-3-acetic acid, indole-3-acetic acid, and indole-3-propionic acid. Peak identification and cross reactivity were checked by the retention time with two hpic systems, Buorometric characterization, and electrochemical characterization. This method is easy and is simple enough for routine analysis.