关键词: 气相色谱-电子捕获, 固相萃取, 复硝酚盐, 水果蔬菜, 液相色谱-质谱

Abstract: A solid-phase extraction coupled with gas chromatography method was developed for the determination of nitrophenol residues in fruits and vegetables. Samples were extracted with methanol-water-H3PO4. The crude extract was purified on HLB solid-phase extraction column, derivatized with acetic anhydride, and re-extracted with n-hexane. The derivatives were determined and confirmed by gas chromatography-election capture detector (GC-ECD). The established method was linear in the range of 0.01–1.0 mg/L. The limit of quantification (LOQ) was 0.01 mg/kg. The recovery rates were in the range of 81.0%–106.6% across three spiked levels (0.01, 0.02 mg/kg and 0.05 mg/kg) in six fruits and vegetables (strawberry, apple, tomato, potato, spinach and aubergine), and the relative standard deviations (RSD) were in the range of 3.9%–8.1%. This method is reliable, stable and suitable for the determination of nitrophenol residue in fruits and vegetables.

Key words: GC-ECD, solid-phase extraction (SPE), sodium nitrophenolates, fruits and vegetables, LC-MS/MS