Abstract:A method was developed for the simultaneous determination of nine plant growth regulator (PGR) residues, such as uniconazole and paclobutrazol, in whole banana fruit, banana pulp, and banana leaves by combining ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and multifunctional needle filter methodology, to provide a reference for the simultaneous determination of multiple PGR residues in bananas. The analytes were extracted from a sample with 1% acetonitrile acetate, and purified by a multifunctional needle filter; the purified sample solutions were analyzed through UPLC-MS/MS in the selective reaction monitoring (SRM) mode for the detection of uniconazole and other PGR residues in the samples. The concentrations of nine PGRs showed good linearity with the corresponding peak area in the 0.001~0.50 mg/L range, and the correlation coefficient (r2) was more than 0.9992. The average recoveries at the spiked levels of 0.05, 0.10 and 0.50 mg/kg for all target compounds in the samples were 80.50%~113.00%, with relative standard deviations (RSD) between 0.40% and 5.60%. The limits of detection (LODs, S/N = 3) for the nine PGRs ranged from 0.20 to 10.00 μg/kg, and the limits of quantification (LOQs, S/N=3), (S/N=10) ranged from 0.70 to 33.50 μg/kg. The proposed method is quick, easy, sensitive and accurate, and can be used for the simultaneous determination of the above-mentioned nine PGR residues in whole bananas, banana pulp, and banana leaves.
