Determination of Nonvolatile Amines in Foods by Liquid Chromatography Following Excimer-forming Fluorescence Derivatization and Solid-Phase Extraction

Abstract

A method for the determination of nonvolatile amines (putrescine, cadaverine, histamine, tyramine and spermidine) in foods by solid-phase extraction and excimer-forming derivatization was investigated. Nonvolatile amines in a solid sample were extracted with 3% trichloroacetic acid, and the amines in a liquid sample were extracted with water. The extract was applied to polymer-based strong cation exchange mini-column, which was then rinsed with phosphate buffer of pH 6.8 and water. Nonvolatile amines were eluted with 100 mmol/L potassium carbonate solution. The solution was mixed with 6 mmol/L 1-pyrenebutylyl chloride solution and derivatized. Derivatives of nonvolatile amines were analyzed by LC-FLD, and the identity of the amines was confirmed by LC-MS/MS without derivatization. The limit of detection (S/N> or =3) of nonvolatile amines in all samples was 0.04 microg/g, and the limit of quantitation (S/N> or =10) was 0.1 microg/g. Recoveries of nonvolatile amines from fish tissues, miso, shoyu and red wine were in the range of 80.4-111%.