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The establishment of a practical method for the determination of piperazine residues using accelerated solvent extraction and UHPLC-FLD

This paper describes a reliable method for estimating piperazine residues in chicken tissues (muscle, kidney, and liver) and pork via ultrahigh-performance liquid chromatography (UHPLC) coupled with a fluorescence detector (FLD) using dansyl chloride (DNS-Cl) as the derivatization reagent. After extraction by accelerated solvent extraction (ASE), the analyte was purified on a strong cation-exchange solid-phase extraction (SPE) column. Separation was achieved using an Acquity UPLC HSS T3 (2.1×100 mm, 1.8 μm) column with ultrapure water-acetonitrile (15:85, V/V) as the mobile phase. The results showed that when the concentrations of piperazine were between the limit of quantitation (LOQ) and 200.0 μg/kg, the peak area of the derivative had a good linear relationship with the piperazine concentration, and the coefficients of determination (R2) were greater than or equal to 0.9991. When the spiked concentration of piperazine was equal to the LOQ, 0.5 MRL (maximum residue limit), 1.0 MRL and 2.0 MRL, the recoveries ranged from 79.64 to 99.77% and the relative standard deviations (RSDs) were 1.14%-5.63%. The limits of detection (LODs) and quantification (LOQs) were 0.50-1.20 μg/kg and 1.80-3.50 μg/kg, respectively. The method was applied to the quantification of piperazine residues in commercial chicken tissues and pork from local supermarkets.