Abstract:

A gas chromatography-mass spectrometry (GC-MS) method was established for the simultaneous determination of nine typical preservatives (pyrimethanil, chlorothalonil, chlorpyrifos, triadimefon, thiabendazole, imazalil, myclobutanil, iprodione, prochloraz) in fruits. The fruit samples were subjected to ultrasonic extraction with hexane/ethyl acetate (1/1, v/v), and followed by purification using diatomite column chromatography with hexane/ethyl acetate (1/3, v/v) eluant. Qualitative and quantitative analysis of the nine preservatives were performed on the GC-MS at full-scan (SCAN) and selected ion monitoring (SIM) modes, in which triphenylphosphate was used as the internal standard. The detection limits obtained for the nine preservatives were ranged from 0.10 μg/kg to 2.16 μg/kg. The average recoveries were in the range of 75.3% to 128% at the spiked levels of 50, 100 and 200 μg/kg with the relative standard deviations (RSDs) of 1.57% to 11.6% (n=5). The results showed that the developed method is sensitive and accurate for the determination of the nine preservatives in fruits.

Key words: fruits, gas chromatography-mass spectrometry (GC-MS), pesticide residue, preservatives