Abstract: A method for the determination of 34 plant growth regulators in vegetables and fruits was established. Samples were pretreated by the quick, easy, cheap, effective, rugged and safe (QuEChERS) method after being ground. Five grams of the samples were extracted with 10 mL of acetonitrile, and dehydrated with a mixture of 4 g of MgSO4, 1 g of NaCl, 1 g of Na3Cit, 0.5 g of 2Na2HCit·3H2O. The supernatant extract was purified with different sorbents according to the state of samples. The analytes were separated on a Waters Acquity HSS T3 column with acetonitrile-water as the mobile phase using gradient elution, detected by mass spectrometry using electrospray ionization with piecewise scanning in the multiple-reaction monitoring (MRM) mode and quantified by the matrix-matched external standard peak area method. The calibration curves were linear in the concentration range of 2–100 μg/kg. The limits of detection (LODs) of 34 plant growth regulators were 2–10 μg/kg. The method was rapid, sensitive and precise, and could meet the requirements for the determination of plant growth regulator residues thereby providing technical support for regulation of plant growth regulator residues in common vegetables and fruits.

Key words: QuEChERS, liquid chromatography-tandem mass spectrometry, plant growth regulators, residue determination