摘要
Abstract
[Objective] To establish a new method of accelerated solvent extraction and gas chromatography mass spectrography to determine the dicloran residue in kown rice. [ Method] The sample was extracted by hexane-acetone (1: 2 by volume) , purified by neutral alumina solid phase extraction column, separated by HP-FFAP silica capillary column with temperature programmed, assessed by GC-NCI-MS in selected ion monitoring mode (SIM) , and quantified by external standard. The experimental conditions including extraction solvent, extraction temperature , different flush volume, static extraction time and cycle number have been optimized. [ Result] When the adding level is 1, 2, 10, 20, 100 μg/kg, the method recovery is 93.6% -102.8% ; the relative standard deviation is 2.2% -6.2% and the detection limit is 1 |xg/kg. The result was determined by comparison to positive sample with retention time and selectively monitoring ion abundances. The accelerated solvent extraction and GC-NCI-MS method purified the brown rice and reduced the analytic time and solvent consumption. [ Conclusion] The experiment successfully established a GC-NC-MS method for determining the dicloran residue in brown rice, which effectively reduces the impact of impurities on the sensitivity of analysis and the detection limit of the method, and improves the specificity of the detection method.关键词
加速溶剂萃取/氯硝胺/残留/糙米/气相色谱-负化学电离源-质谱法Key words
Accelerated solvent extraction/ Dicloran/ Residue/ Brown rice/ Gas chromatography-negative chemical ionization-mass spec-trometry分类
农业科技
