微波提取-高效液相色谱法测定食用菌中百草枯

Determination of Paraquat in Edible Fungi by Microwave Extraction-High Performance Liquid Chromatography

建立百草枯在食用菌中的高效液相色谱残留分析方法。样品用10mL浓度2mol/L的盐酸溶液120℃微波消解提取30min,提取液经强阳离子交换(SCX)固相萃取小柱净化,氯化铵饱和溶液洗脱并定容。采用AtlantisHILIC Silica色谱柱,乙腈-辛烷基磺酸钠缓冲液为流动相,紫外检测波长259nm。该方法百草枯定量限为1.0μg/kg(RSN=10)。百草枯的添加回收率为82.33%～96.99%,相对标准偏差为1.23%～3.90%,该方法适合于食用菌中百草枯残留快速分析。

An HPLC method was established for the determination of paraquat residues in edible fungi. Samples were extracted with 10 mL of hydrochloric acid solution by microwave digestion extraction at 120 ℃ for 30 min, cleaned- up by strong cation exchange （SCX） solid-phase extraction （SPE） column and eluted by saturated ammonium chloride. HPLC separation was carried out by reverse phase chromatography on Atlantis HILIC silica column with a mobile phase composed of acetonitrile and actyl sulfonate at the ratio of 40：60. Paraquat was detected by ultraviolet detector at 259 nm. The limit of quantification （LOQ） based on 10 times signal-to-noise was 1.0 μg/kg. The recovery rate was in the range of 82.33%-96.99% with the relative standard deviations （RSD） of 1.23%-3.90%. This established method is satisfactory for the determination of paraquat residues in edible fungi.