Abstract:A dispersive solid phase extraction coupled with high performance liquid chromatography tandem mass spectrometry method with dispersive solid phase extraction was established for the determination of γnonanolactone in coconut juice.The effect of extration condition，flow phase，and tandem mass spectrometry parameters were investigated.And the possible fragmentation mechanisms of γ-nonanolactone were presumed.The sample was extracted with acetonitrile and determined under the multiple reaction monitoring（MRM）mode by employing external method.The precursor-product ion pair m/z 157.1/139.1 was selected as qualitative ions，and m/z 157.1/121.1 was selected as quantitaive ion.The calibration curve was linear in the range of 0.025 μg/mL～0.50 μg/mL.The limits of detection were 0.025 μg/mL for the instrument and 0.10 mg/kg for the method respec tively.The LOQ was 0.40 mg/kg for the method.The average recoveries of γ-nonanolactone were between 92.4%and 98.4%at spiked levels of 0.10，0.20 mg/kg and 0.40 mg/kg with relative standard derivation（RSDs）of 6.8%～7.6%（n=10）.