Determination of nitrofuran metabolites in seafood by ultra high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry

A new analytical method has been developed for the simultaneous determination of 4 nitrofuran metabolites in seafood by ultra-high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC–QqQ-MS/MS). The extraction procedure was based on a simultaneous acidic hydrolysis and derivatization using 2-nitrobenzaldehyde (2-NBA), followed by a solid-phase extraction (SPE). Recovery was studied by spiking blank samples at two concentration levels (1 and 10 μg/kg) and recoveries ranged from 73 to 100% and 79 to 103%, respectively. Precision values, expressed as relative standard deviation (RSD) were ≤19% and ≤23% for intra-day and inter-day precision, respectively. Linearity was studied in the range 1–50 μg/kg and the obtained determination coefficients (R2) were ≥0.9900 for all compounds. Limits of detection (LODs) for the derivatized nitrofuran metabolites were 0.5–0.8 μg/kg and limits of quantification (LOQs) were established at 1 μg/kg, whereas decision limit (CCα) and detection capability (CCβ) ranged from 1.5 to 2.6 μg/kg and 1.6 to 3.1 μg/kg, respectively. Finally, the method was applied to real food samples, but nitrofurans were not found.