超声辅助萃取气相色谱-质谱法测定松针中的多溴联苯醚

建立了测定松针样品中多溴联苯醚(PBDEs)的分析方法。松针样品经过正己烷-丙酮(体积比为1∶1)混合溶液超声萃取、浓硫酸和氧化铝柱净化后，采用气相色谱-负化学电离源质谱(GC-NCI-MS)选择离子监测(SIM)模式检测，内标法定量。结果表明，方法的加标回收率为83.8%~107.5%，三溴~七溴代联苯醚的仪器检出限为0.152~ 0.770 pg，十溴代联苯醚(BDE-209)的检出限为11.1 pg；三溴~七溴代联苯醚的方法检出限(湿重)为3~15 pg/g，BDE-209的方法检出限(湿重)为222 pg/g。方法具有良好的重现性、较高的灵敏度和良好的回收率。实际样品分析表明，松针中BDE-209是主要的同类物，约占8种PBDEs总量的82.3%，低溴代联苯醚以2,2′,4,4′-四溴联苯醚(BDE-47)为主。

Determination of polybrominated diphenyl ethers in pine needles using ultrasonic-assisted extraction and gas chromatography-negative chemical ionization-mass spectrometry

A method for the determination of polybrominated diphenyl ethers (PBDEs) in pine needles was developed. Ultrasonic-assisted extraction (UAE) was employed with n-hexane-acetone （1∶1, v/v), and concentrated H2SO4 and an alumina column were used for cleaning-up the extract of pine needles. The final extract was identified and quantified for the 8 PBDE congeners（BDE-28, 47, 99, 100, 153, 154, 183, and 209） by gas chromatography-negative chemical ionization-mass spectrometry (GC-NCI-MS) with internal standard method in the selective ion monitoring (SIM) mode. The recoveries of the spiked standards ranged from 83.8% to 107.5%. The instrumental detection limits for tri- to hepta-BDEs (BDE-28, 47, 99, 100, 153, 154 and 183) were in the range of 0.152-0.770 pg, and for BDE-209 was 11.1 pg. The method detection limits for the above-mentioned PBDEs were 3-15 pg/g wet weight and 222 pg/g wet weight, respectively. The results indicate that the method has high sensitivity, satisfactory recovery and good reproducibility. BDE-209 was found to be the dominant congener (82.3% of the total of 8 PBDEs), and BDE-47 was the major congener among the lower brominated congeners.