基质固相分散萃取-分散液相微萃取-气相色谱/质谱联用法测定土壤中的邻苯二甲酸酯

Determination of five phthalic acid esters in soil by matrix solid phase dispersion extraction-dispersive liquid-liquid microextraction-gas chromatography-mass spectrometry

建立了基质固相分散萃取-分散液相微萃取-气相色谱质谱联用法测定土壤中5种邻苯二甲酸酯的分析方法。优化了前处理条件,最佳条件为：0.2g样品与0.4g弗罗里硅土研磨8min,混合物以10mL丙酮-乙酸乙酯（1：1,V：V）洗脱,用氮气吹干并用乙腈定容至0.4mL,加入30μL四氯化碳和5mL超纯水形成乳化,离心破乳后吸取1μL沉积相进GC-MS分析。DMP在25~500μg/kg,DEP在10~500μg/kg,DBP、BBP和DNOP在5~500μg/kg范围内线性关系良好,相关系数在0.9983~0.9997,检出限为0.32~2.90μg/kg,平均加标回收率为85.5%~104%,相对标准偏差（n=5）小于8.2%。方法满足实际土壤中微量邻苯二甲酸酯分析的要求。

A matrix solid-phase dispersion extraction-dispersed liquid phase microextraction-gas chromatography mass spectrometry method has been developed for the determination of five phthalic acid esters （PAEs） in soil. Several conditions were optimized. The best conditions as follows： 0. 2 g soil and 0. 4 g Florisil was grinding for 8 min. The mixture was eluted with 10 mL of acetone-ethyl acetate（ 1： 1, V： V）. The eluent was dried by nitrogen and resolved 0. 4 mL acetonitrile, and then mixed with 30 μL of tetrachloromethane and 5.0 mL of ultrapure water to form a homogeneous cloudy solution. The emulsion was broken by centrifugation. 1 μL sediment phase was injected and analyzed directly by GC-MS. Linearities of the five PAEs was good from 25 to 500 μg/kg for DMP, from 10 to 500 μg/kg for DEP, from 5 to 500 μg/kg for DBP, BBP and DNOP. The correlation coefficients ranged from 0. 9989 to 0. 9997, and average recoveries at two spiked levels were ranged of 85.5% ~ 104% with RSD less than 8.2% （ n = 5 ）. The LODs of five PAEs were 0. 32 - 2. 90 μg/kg. This method is rapid, and simple, can meet the determination of trace PAEs in soil.