建立了同时测定土壤中7种多溴联苯醚(PBDEs)的超声微波协同萃取/气相色谱测定方法.考察了萃取溶剂的种类和用量、微波功率、萃取时间等因素对模拟土壤中PBDEs回收率的影响,得到了最佳萃取条件:萃取剂为50 mL正己烷-丙酮(1:1),微波辐射功率为90W,萃取时间为10 min.在最佳条件下,PB-DEs在10～400 μg·L-1范围内呈良好线性,相关系数(r2)为0.999 1～0.9997;检出限为0.21～0.63 ng ·g-1.模拟土样中7种PBDEs的回收率为75％～ 121％,相对标准偏差为5.2％ ～ 7.8％.将该方法用于上海崇明岛东滩湿地实际土样中PBDEs的测定,样品检出BDE-28和BDE-47,且所得结果与索氏提取法相当.方法操作简单、效果好、灵敏度高,适用于土样中PBDEs的测定.%An ultrasound/microwave assisted extraction and gas chromatography with electron capture detector ( GC/ECD) was developed for the simultaneous determination of seven polybrominated di phenyl ethers( PBDEs) in soil. The influences of several parameters, such as the type and dosage of solvent, microwave power and time of extraction, on the extraction efficiencies were investigated. The optimal operation conditions were as follows; extraction solvent; 50 mL n-hexane - acetone (1 : 1), microwave power; 90 W, and extraction time; 10 min. Under the optimal extraction con ditions, good linear relationships were obtained in the concentrations of 10 -400 μg ? L-1 for all the analytes with correlation coefficients(r2) of 0. 999 1-0. 999 7. The limits of detection were between 0. 21 ng ? G-1 and 0. 63 ng ? G-1. The spiked recoveries of PBDEs in soil were between 75% and 121% with relative standard deviations (RSDs) of 5. 2% -7. 8% . The proposed method was applied in the determination of PBDEs in wetland soil samples collected from Chongming Island of Shanghai, in which two PBDEs (e. G. BDE-28 and BDE-47) were found. The results were in agreement with those obtained by the Soxhlet - GC method. With the advantages of simple procedures, good sensitivity and high accuracy, this method could be used for the monitoring of PBDEs in soils.
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