Determination of Plant Hormones Residues in Food by Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

[Aims]A method was established for determining plant hormones residues in food by ultra performance liquid chromatography-tandem mass spectrometry(UPLC/MS/MS).[Methods] The samples were extracted with methanol-water(90∶10,by vol),and cleaned up by WCX cartridge.The target analytes were separated by Waters C18 column with gradient elution using acetonitrile and 0.1% formate in water as mobile phases.Positive electrospray ionization with multiple reaction monitoring mode was used in the detection.External standard method was used to determine the results.[Results] In the linear range(1-100 μg/L) of each plant hormones,the correlation coefficient was greater than 0.997 for each plant hormones.The limit of detection(LOD) were 0.3-0.5 μg/kg,and the limit of quantitation(LOQ) were 1.0-1.5 μg/kg.In the range of 5-20 μg/kg,the corresponding recoveries were 80.2-119.3%.The relative standard deviation(RSD) of intra-day and inter-day were 0.65-7.28%.[Conclusions] The simplicity,sensitivity and good precision of the method made it be well suitable for determination of plant hormones residues in food.