Abstract: In this paper, polyethersulfone (PES)/multi-walled carbon nanotubes (MWCNTs) composite membrane was prepared by phase inversion method, and its surface morphology and structure were observed by scanning electron microscopy (SEM). The results showed that the membrane displayed a finger-shaped porous structure. A simple, easy-to-operate filtration device equipped with the composite membrane was designed and used to develop a rapid sample pretreatment for the analysis of 15 pesticide residues in food by ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Good sample cleanup was obtained with the composite membrane. However, due to the special planar ring structure of multi-walled carbon nanotubes incorporated in it, the composite membrane could adsorb planar pesticides. Consequently, of the 15 pesticides analyzed, the average recoveries of two planar pesticides were low while those of the other pesticides were between 71% and 118%, with relative standard deviation (RSD) between 0.73% and 12.87% (n = 6). The method reduced the overall sample preparation time from 4–7 h to 30 min. The method was simple, efficient, sensitive and environmentally friendly and could be applied widely. It was suitable for rapid analysis of non-planar pesticide residues in food.

Key words: polyethersulfone (PES)/multi-walled carbon nanotubes (MWCNTs) composite membrane, food, pesticide residues, ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), determination