Evaluation of biogenic amines in fish sauce by derivatization with 3,5-dinitrobenzoyl chloride and micellar liquid chromatography

A simple, selective and sensitive method to quantify the biogenic amines cadaverine, 2-phenylethylamine, histamine and spermidine has been developed. The analytes were derivatized with 3,5-dinitrobenzoyl chloride and separated by micellar liquid chromatography. This is a practical technique for the selective determination and quantification of biogenic amines in fish sauce. Optimization of chromatographic conditions was made by an interpretative model, and the separation conditions were: C18 column (125 mm × 4.6 mm, 5 μm particle size), UV detection set at 260 nm, and a mobile phase of 0.15 mol L−1 sodium dodecyl sulfate (SDS), pH 7. Validation was performed following the United States Food and Drug Administration (FDA) guidelines using spiked samples. Under these conditions, validation parameters were: linearity (0.5–500 μg mL−1, r2 > 0.9990), limits of detection (in the 158–375 ng mL−1 range); intra and inter-day precision (relative standard deviation < 3.2% and 4.2%) and accuracy (in the range of 88.6–103.7% and 94.2–101.5%), respectively, and variations were lower than 4%. The proposed method was successfully applied to the monitorization of biogenic amines formation in unsalted and salted fish sauce samples. The suggested methodology was found useful in routine analysis of biogenic amines in fish sauce.