全自动加速溶剂萃取结合固相萃取-高效液相色谱-串联质谱法测定果树种植土壤中3种喹啉类杀菌剂的残留量

Determination of Residues of 3 Quinoline Fungicides in Fruit Tree Planting Soil by High Performance Liquid Chromatography-Tandem Mass Spectrometry with Fully Automatic Accelerated Solvent Extraction and Solid Phase Extraction

提出了全自动加速溶剂萃取结合固相萃取-高效液相色谱-串联质谱法(HPLC-MS/MS)测定果树种植土壤中灭螨猛、二氰蒽醌、乙氧喹啉等3种喹啉类杀菌剂残留量的方法。取预处理后的土壤样品粉末10.0 g,加入硅藻土约10 g,混匀后置于加速溶剂萃取池中,在萃取温度70℃,萃取时间8 min下进行萃取,得到的提取液氮吹至5 mL,然后用活化好的HLB固相萃取柱进行净化。经过淋洗、洗脱后,将洗脱液氮吹至近干,用乙腈定容至1 mL,过0.45μm滤膜。采用HPLC-MS/MS测定滤液中3种喹啉类杀菌剂的含量。以Shimadzu Venusil MP C_(18)色谱柱为固定相,以不同体积比的0.1%(体积分数)甲酸溶液和甲醇混合溶液为流动相进行梯度洗脱;分离后的目标物经电喷雾离子源正离子模式扫描,多反应监测模式检测。结果表明:3种目标物的质量浓度均在一定范围内与对应的响应值呈线性关系,检出限(3S/N)为0.05~0.13μg·kg^(-1);3个加标浓度水平下,目标物的回收率为87.3%~103%,测定值的相对标准偏差(n=6)均小于4.0%。

A method for the determination of residues of 3 quinoline fungicides,including chinomethionat,dichloroanthraquinone and ethoxyquin,in fruit tree planting soil by high performance liquid chromatography-tandem mass spectrometry with fully automatic accelerated solvent extraction and solid phase extraction.The pretreated soil sample powder(10.0 g)was taken,and about 10 g of diatomite was added.After mixing well,the mixture was placed into a accelerated solvent extraction tank,and the extraction was conducted at extraction temperature of 70℃and extraction time of 8 min.The extracting solution was blown to 5 mL by nitrogen,then purified by activated HLB solid phase extraction column.After rinsing and eluting,the eluate was blown to near dryness by nitrogen,and its volume was made up to 1 mL with acetonitrile.The mixed solution was filtered by 0.45μm filter membrane,and 3 quinoline fungicides in the filtrate was determined by HPLC-MS/MS,using Shimadzu Venusil MP C18 column as the stationary phase,and the mixed solution of 0.1%(volume fraction)formic acid solution and methanol at different volume ratios as the mobile phase for gradient elution.Targets seperated were scanned by the positive ion mode of the electrospray ion source,and deteted by the multiple reaction monitoring mode.It was shown that linear relationships between the mass concentrations and corresponding response values of the 3 targets were kept in definite ranges,with detection limits(3S/N)in the range of 0.05-0.13μg·kg-1.The recovery of the 3 targets ranged from 87.3%to 103%at 3 spiked concentration levels,with RSDs(n=6)of the determined values less than 4.0%.