Rapid Determination of Dichlofluanid Residues in Vegetables Using Dispersive-SPE Sample Preparation Combined with Gas Chromatography–Mass Spectrometry

摘要

A method for rapid determination of dichlofluanid residue in vegetables using dispersive solid-phase extraction (dispersive-SPE) sample preparation combined with gas chromatography–mass spectrometry (GC–MS) was developed. Samples were extracted with actone–ethyl acetate (1:1, V/V), and then detected by GC–MS with an external standard method after being purified by optimized primary secondary amine, graphitized carbon black and anhydrous magnesium sulphate (MgSO4). It turned out that dichlofluanid showed a good linearity (y = 2.7E + 5x− 2710.5) over the range of 0.02–2.00 mg/L with a correlation coefficient of 0.9994. The limit of detection was 0.13 μg/kg (S/N = 3) and the limit of quantification was 0.43 µg/kg (S/N = 10). The recoveries of the dichlofluanid were in the range of 73.3–106.7, 83.3–116.7 and 83.3∼106.7% with the spiked levels of 0.01, 0.02 and 0.05 mg/kg, and the relative standard deviations were in the range of 4.1–22.3%. Compared with the reported literature, the method is more simple, rapid, sensitive, reliable and can be applied to many vegetables.