食品印刷包装材料中多氯联苯的气相色谱-串联质谱法测定及其基质效应探讨

Determination of polychlorinated biphenyls in food packaging materials by gas chromatograph-tandem mass spectrometric and discussion of matrix effects

建立了气相色谱一串联质谱法检测食品印刷包装材料中7种指示性多氯联苯（PCBs）的分析方法，考察了基质效应的影响，用浓硫酸和N-丙基乙二胺（PSA）净化基质，发现基质匹配校准法可有效地避免基质增强效应。实验采用超声萃取法提取样品，经过浓硫酸净化、浓缩定容后，用气相色谱-串联四极杆质谱仪在多反应监测模式（MRM）下进行测定。在0．08～10μg/L浓度范围内，由锯／塑、纸／纸复合材料配制的基质标准曲线均呈现出良好线性，线性相关系数大于0.9984，方法的检出限为0．06—0．18ng／g，在2ng／g和10ng／g加标水平下，平均回收率为84．52％～107．21％，相对标准偏差为1．4％～8．0％。方法能消除复杂基质的干扰，可用于食品印刷包装材料中痕量多氯联苯的测定。

A gas chromatography-tandem mass spectrometric （GC-MS/MS） method was established for the de- termination of 7 specified polychlorinated biphenyls （PCBs） in food packaging materials. The matrix effect was investigated and the corresponding solutions were discussed. Concentrated sulfuric acid and cleanert PSA were used to purify the matrix. After that, the matrix-match calibration method was tested and proved to be an effec- tive way, which could reduce matrix-induced response enhancement. In this experiment, PCBs were extracted from packaging material samples by solvent ultrasonication, followed by purification of concentrated sulphuric acid. After concentrated to the defined volume, it was analyzed by GC-MS/MS in the multiple-reaction monito- ring （MRM） mode. In the concentration range of 0. 08 ~ 10 μg/L, the matrix calibration curves prepared by po-lyethylene-aluminnum and paper-paper composite materials gave good linearity with correlation coefficients longer than 0. 9984. The limits of quantification （LOQ） were in the range of 0. 06 ~ 0. 18ng/g. At the spiked levels of 2, 10ng/g, the mean reeoveries were in the range of 84. 5% ~ 107.2%, with relative standard deviations （RS- Ds） of 1.4% ~ 8.0%. The accuracy and reliability of the method made it suitable for the residue determination of PCBs in food packaging materials.