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Determination of Histamine in Wine Samples by Flow-Injection Analysis and Multivariate Calibration

A flow injection method for the rapid determination of histamine in wines is proposed. This method is based on the reaction of the analyte with 1,2-naphthoquinone-4-sulfonate to form a derivative detected by UV-Vis absorption spectroscopy. The amine derivatization is carried out at pH 9.2 in a PTFE coil heated at 60°C. Experimental conditions are not able to provide selectivity for histamine with respect to other amino compounds so that its response is interfered with by other amines and amino acids present in the wine matrix. Here, multivariate calibration methods have been used to overcome the lack of selectivity. As a result, wines can be directly analyzed without removing interferences. For this purpose, spectra taken at the peak maximum have been used as multivariate data to be further analyzed with partial least square regression. The number of significant latent variables to be used in the construction of the calibration models as well as a preliminary evaluation of the prediction performance have been estimated by leave-one-out cross validation. The quantification of histamine concentrations in wine samples is satisfactory with an overall prediction error about 5%.