气相色谱-质谱法检测沉积物中自由态与束缚态多溴联苯醚和四溴双酚-A

建立了一种同时测定沉积物中不同赋存形态的多溴联苯醚(PBDEs)和四溴双酚A(TBBPA)的分析方法.样品由等体积的丙酮和正己烷混合溶剂抽提得到自由态目标物,再通过碱性水解反应释放束缚态目标化合物.通过调节酸度(pH值)实现PBDEs和TBBPA的分离和提取.PBDEs由复合硅胶柱净化,运用气相色谱-质谱(负离子化学源)-分时段选择离子监测技术测定;TBBPA经重氮甲烷衍生化反应后由酸性硅胶柱预纯化,运用气相色谱-质谱(电子轰击源)-分时段选择离子监测技术测定.8种低溴联苯醚(BDE28,-47,-66,-100,-99,-154,-153,-183),十溴联苯醚(BDE209)和TBBPA的检出限分别为0.6～12.5 pg/g,172 pg/g,4 2 pg/g.方法具有良好的准确度和精确度,回收率均在74%～106%之间,RSD≤10%.对东江沉积物样品的分析表明,本方法能够实现不同形态的PBDEs 和TBBPA的有效检测.

Analysis of Free and Bound Residues of Polybrominated Diphenyl Ethers and Tetrabromobisphenol A in Sediment

An analysis method was developed for the determination of free and bound fractions of polybromi-nated ethers (PBDEs) and tetrabromobisphenol A (TBBPA) in sediment. The free PBDE and TBBPA were extracted with acetone/hexane ( 1:1) mixed solvent,and the bound fraction was released from the sediment by saponification reaction at 80℃. PBDEs and TBBPA were separated via adjusting pH; PBDEs were determined by GC-negative chemical ionization (NCl)-MS after cleaned up by multilayer silica column,and TBBPA was derivative before pre-separated by acid silica column and finally determined by GC-EI-MS. All of the target compounds were quantitative by internal standard method. The limits of detection of eight low bromina-ted congeners (BDE28,-47,-66,-100,-99,-154,-153 and -183),deca-BDE ( BDE209),and TBBPA were 0.6 - 12.5 pg/g,172 pg/g and 4. 2 pg/g,respectively;This method is reliable and stable. The recoveries of all compounds were ranged from 74% to 106% and the relative standard deviations were below 10%. This method is suitable for the measurement of different forms of PBDEs and TBBPA in sediment under reliable quality assurance and quality control.