Simultaneous derivatization and liquid-solid phase transition microextraction of six biogenic amines in foods followed by narrowbore liquid chromatography-ultraviolet detection
Biogenic amines are quality control criteria for foods that are potentially toxic to humans. In this study, amidation derivatization for biogenic amines and liquid-solid phase transition microextraction were carried out simultaneously for food sample pretreatment. The derivatization reaction was executed in one pot with coumarin-3-carboxylic acid as the derivatizing reagent and (1-cyano-2-ethoxy-2-oxoethylidenaminooxy)dimethylamino-morpholino-carbenium hexafluorophosphate as the coupling agent. Liquid-solid phase transition microextraction was achieved by the salting-out effect, using a phase change salt (1 M disodium hydrogen phosphate) solution. The combined derivatization and microextraction process was completed within 3 min at 30 °C, and the liquid top phase was easily obtained by placing the tube in an ice bath. Finally, a narrowbore liquid chromatograph coupled with a UV detector was used to determine the levels of six biogenic amines. The coupling agent-assisted derivatization and liquid-solid phase transition microextraction parameters were also investigated. The quantitative linear ranges were 3-400 μM for histamine, putrescine, spermidine, cadaverine, and tyramine and 5-400 μM for spermine, and the detection limit was 1 μM. The relative standard deviations of the intra- and inter-batches were <5.3% and 8.4%, respectively, while the relative error was <4.5% for both. We successfully applied this simultaneous derivatization-microextraction method to determine the biogenic amines in fermented foods.