Dansyl Chloride as a Derivatizing Agent for the Analysis of Biogenic Amines by CZE-UV

Biogenic amines (BAs) are important compounds that can be used in the quality control of food and beverages. BA analysis is a challenging task that can be made easier by applying a derivatizing agent like dansyl chloride (DNS). The optimized capillary zone electrophoresis (CZE) separation of the DNS-BA derivates (derivates of cadaverine, histamine, putrescine, tryptamine, and tyramine) was performed using benzylamine as an internal standard, a potential of 18 kV, a temperature of 23 °C, a running buffer consisting of phosphoric acid, 120 mmol L−1, pH 2.5, and an hydrodynamic injection at 25 mBar for 6 s. All calibration curves had r2 higher than 0.99, and limits of detection (LODs) ranged from 7 to 50 µg L−1. The developed methodology was tested in cheese and yogurt samples. DNS showed to be an alternative derivatization reagent not only because it produced UV-detectable derivates (214 nm), but also because of its stability, aqueous solubility, high selectivity and sensitivity, reduced impurities, and simple preparation steps.