Abstract:
A liquid chromatography with electrospray tandem mass spectrometry method was developed for quantitative determination of 2-aminobenzimidazole, carbendazim, triabendazole, thiophanate-methyl in concentrated fruit juice. Apple, mango, pineapple, pear, orange, lychee, passion fruit juice concentrate were selected as samples. The samples were extracted by acetonitrile and purified by PSA column. With methanol-10mmol/L ammonium acetate (containing 0.1% volume concentration of formic acid) as mobile phase gradient elution, extractions of samples were separated by ZORBAX Eclipse XDB-C18 column and detected by electrospray tandem mass spectrometry with ESI+ and multiple reaction monitoring (MRM) modes. Results showed that the mean recoveries ranged from 70.3%~109.8% with relative standard deviations in the range of 0.1%~10.9% when the spiked concentrations of 2-amino-benzimidazole were 2, 4, 20μg/kg and thiophene benomyl, carbendazim, thiophanate-methyl were 1, 2, 10μg/kg respectively. And the limits of detections of 2-amino-benzimidazole, carbendazim, thiabendazole, thiophanate-methyl were 2, 1, 1, 1μg/kg. This method can be used to accurately and efficiently detect these four fungicides residues in concentrated fruit juice so it can be an important measure to monitor and control the quality of concentrated fruit juice.