Determination of biogenic amines in tomato by ion-pair chromatography coupled to an amine-selective potentiometric detector

Abstract

It is described the determination of underivatized biogenic amines by ion-pair chromatography coupled to potentiometric detection, for food quality control. A wall-jet flow-cell was used to hold an amine-selective electrode, based on cucurbit[6]uril as an ionophore, and a commercial reference electrode. The biogenic amines were separated in less than 20 min using a C18 column as the stationary phase. This method comprises a gradient elution with a mobile phase containing lithium formate buffer, acetonitrile, and butane-sulfonic acid sodium salt as an ion-pair agent. The proposed method was validated following the International Council for harmonization guidelines. Calibration data fitted a linear regression model with R2 varying from 0.9804 to 0.9972. Repeatability intra and inter-day showed relative standard deviation values lower than 9.1% and 13.3%, respectively. Detection and quantification limits ranged from 0.03 to 0.20 mg L−1 and 0.09 to 0.61 mg L−1, respectively. Spiked tomato samples were analysed to assess the accuracy, yielding recovery values from 85.8 to 108.5%. The biogenic amines content in fresh tomatoes, canned chopped tomato, and pulp tomato was 7.11, 5.12, and 7.69 mg L−1, respectively.