Novel fluorescence labeling reagent 4-(carbazole-9-yl)-benzyl chloroformate and its application in the determination of nitrofuran metabolites compounds in foodstuffs by high performance liquid chromatography with fluorescence detection

Abstract

The goal of the presented work is to develop a simple and sensitive high-performance liquid chromatography in combination with fluorescence detection (HPLC-FLD) method for the determination of four nitrofurans (NFs) metabolites compounds (semicarbazide (SEM), 1-aminohydantoin (AH), 3-amino-2-oxazolidinone (AOZ) and 3-amino-morpholinomethyl-2-oxazolidinone (AMOZ)) in foodstuffs. For this goal, we synthesized a novel fluorescence labeling reagent, 4-(carbazole-9-yl)-benzyl chloroformate (CBBC) to label NFs metabolites compounds. NFs metabolites compounds can be labeled rapidly only within 5 min at the room temperature (25 °C). The labeled derivatives showed excellent fluorescence property with maximum excitation and emission wavelengths of 375 nm and 410 nm, respectively. The labeled derivatives were analyzed on a reversed-phase Eclipse XDB-C18 column within 10 min. Excellent linearity (R2 > 0.995) of all NFs metabolites compounds was achieved with the limits of detection (LODs) and the limits of quantitations (LOQs) in the low micrograms per kilogram range of 0.20–0.30 μg·kg−1 and 0.70–1.00 μg·kg−1, respectively. Satisfactory recoveries in the range of 92.5–98.0% were obtained for all NFs metabolites compounds. Using the proposed HPLC-FLD method, we successfully determined four NFs metabolites compounds in different foodstuffs. As promising, this highly sensitive and reliable method would also be extended for the quantitation of NFs metabolites compounds in other samples.