复杂基质样品中邻苯二甲酸酯测定的样品前处理

对不同类型复杂基质样品中邻苯二甲酸酯(PAEs)测定的前处理方法进行了研究。待测样品类型包括沉积物、土壤、悬浮颗粒物、地表灰尘、生物组织、化妆品、皮革、塑料以及近岸/河口海水等复杂基质样品。这些样品中PAEs测定的最常用方法为气相色谱-质谱法(GC-MS),针对该测定方法所需的样品前处理研究集中于待测PAEs的萃取、净化等步骤操作条件的确定。对各种样品基质前处理方法的研究结果表明,二氯甲烷是进行固液萃取时最佳的超声振荡提取溶剂;而对各种复杂基质样品的净化,硅胶则是经济、实用的固相萃取填料;C18是最常用的近岸/河口海水样品中PAEs的预富集填料;一定比例的正己烷与乙酸乙酯混合溶液是适宜的固相萃取洗脱液。优化实验条件下,各种样品基质中PAEs的加标回收率高于58%,方法相对标准偏差(RSD)小于10.5%(n=6);方法对沉积物样品中PAEs的检出限(DL,3σ)最低,在0.3 μg/kg(邻苯二甲酸二丁酯)~5.2 μg/kg(邻苯二甲酸二异壬酯)之间;对近岸/河口海水样品的检出限(DL,3σ)在6 ng/L(邻苯二甲酸二丙酯)~67 ng/L(邻苯二甲酸二异癸酯)之间,能满足上述各类复杂基质样品中16种PAEs测定的需要。

Sample pretreatment for the measurement of phthalate esters in complex matrices

Sample pretreatment methods for the measurement of phthalate esters (PAEs) by gas chromatography-mass spectrometry (GC-MS) in various complex matrices, including sediment, soil, suspended particle matter, urban surface dust, Sinonovacula Constricta, cosmetic, leather, plastic and coastal/estuarine seawater, were proposed. The pretreatment which was appropriate for GC-MS detection was focused on the investigation and optimization of operating parameters for the extraction and purification, such as the extraction solvent, the eluant and the adsorbent of solid phase extraction. The results of the study of pretreatment for various complex matrices showed that methylene chloride was the best solvent for the ultrasonic extraction when solid-liquid extraction was used; silica gel was the economical and practical adsorbent for solid-phase extraction for purification; C18 was the most commonly adsorbent for preconcentration of PAE in coastal/estuarine seawater sample; the mixed solution of n-hexane and ethyl acetate with a certain proportion was the suitable SPE eluent. Under the optimized conditions, the spiked recoveries were above 58% and the relative standard deviations (RSDs) were less than 10.5% (n=6). The detection limits (DL, 3σ) were in the range of 0.3 μg/kg (dibutyl phthalate)-5.2 μg/kg (diisononyl phthalate) for sediment, and 6 ng/L (dipropyl phthalate)-67 ng/L (diisodecyl phthalate) for costal/estuarine seawater. The pretreatment method for various complex matrices is prominent for the measurement of the 16 PAEs with GC-MS.