五氟苯甲酰氯衍生色谱法分析水体中痕量羟基多溴联苯醚

以五氟苯甲酰氯(PFBCl)作为衍生化试剂,气相色谱-电子捕获检测器(Gas chromatography-electron capture detector,GC-ECD)为检测手段,建立了水体中痕量羟基多溴联苯醚(Hydroxylated polybrominated diphenyl ethers,简称OH-PBDEs)的酰基化衍生-GC/ECD检测方法.通过实验讨论了衍生化缓冲溶液、衍生化时间以及衍生后萃取溶液异辛烷的用量对检测结果的影响,确定了最佳的衍生化条件.在最佳的衍生化条件下,4-OH-BDE 42、4’-OH-BDE 49、6-OH-BDE 47、2’-OH-BDE 68和6’-OH-BDE 99的衍生化产物均获得了良好的分离度和色谱响应值.本方法的仪器检出限为0.02—0.14 pg,方法检出限为0.61—4.67 pg.L-1,标准曲线线性相关系数的范围为0.9973—0.9996,相对标准偏差均小于10%.3种采自大连市不同地区环境水样的加标回收率检测结果表明,所建立的分析方法适于水体中痕量OH-PBDEs的检测.

Determination of trace hydroxylated polybrominated diphenyl ethers in water by pentafluorobenzoyl chloride derivatization and gas chromatography

The pentafluorobenzoyl chloride(PFBCl) derivatization method coupled with gas chromatography-electron capture detector(GC-ECD) was established to analyze the hydroxylated polybrominated diphenyl ethers(OH-PBDEs) in water.The conditions for the PFBCl derivatization of OH-PBDEs at trace level in water samples were optimized.The optimal conditions were obtained as follow: the derivatization buffer solvent of mixed acetonitrile/methanol/water/pyridine solution 150 μL,extraction solvent(isooctane,after the derivatization was realized) 1mL and derivatization time 10 min.The instrument detection limits for these OH-PBDEs(4-OH-BDE 42,4′-OH-BDE 49,6-OH-BDE 47,2′-OH-BDE 68,and 6′-OH-BDE 99) were from 0.02 to 0.14 pg,and the method detection limits ranged from 0.61 to 4.67 pg·L-1 under the optimal conditions.The correlation coefficients of the standard curve were from 0.9973 to 0.9996,and the relative standard deviations were less than 10%.The results for the detection of OH-PBDEs in spiked actual water samples showed that this method had satisfactory recoveries for the OH-PBDEs derivatives,indicating that this method was suitable for determination of trace OH-PBDEs in water.