Rapid and convenient determination of α-dicarbonyl compounds via streamlined simultaneous derivatization and extraction coupled with liquid chromatography-fluorescence detection

Abstract

α-Dicarbonyl compounds (α-DCs), formed during food heating and storage, are crucial for assessing food safety and quality. However, the low concentration, high reactivity, and absence of chromophores of α-DCs make their detection challenging, often requiring complex derivatization and extraction. This study developed a one-pot method for α-DCs that combines derivatization and magnetic solid-phase extraction. By mixing the sample, 2,3-diaminonaphthalene, and Fe₃O₄/MWCNTs-OH in a vial, simultaneous derivatization and extraction are achieved. Derivatization converts α-DCs into hydrophobic products, facilitating their adsorption and enabling sensitive liquid chromatography-fluorescence detection. The introduction of the magnetic adsorbent allows phase separation to be easily achieved using an external magnet, simplifying and speeding up the process. The detection limits for six α-DCs (glyoxal, methylglyoxal, diacetyl, 2,3-pentanedione, D-glucosone, and 3-deoxyglucosone) were determined to be in the range of 0.4–3.5 nM. This rapid and convenient analytical approach was successfully applied to analyze α-DCs in juices, coffees, and tea beverages.