超高效液相色谱-四极杆-飞行时间质谱法筛查塑料玩具中邻苯二甲酸酯类增塑剂

摘要

建立了塑料玩具中15种邻苯二甲酸酯类增塑剂的超高效液相色谱-四极杆-飞行时间质谱(UPLC-Q-TOF MS)筛查与定量检测方法.不同基质的塑料玩具样品采用溶剂溶解-超声提取-沉淀分离,经石墨化碳固相萃取柱净化、旋转蒸发和氮吹浓缩后,以C18柱(2.1 mm×50 mm,1.7 μm)梯度洗脱分离,在电喷雾正离子及一级全扫描和信息相关二级全扫描模式下检测.以一级精确质量数、同位素分布、保留时间及二级质谱与数据库匹配结果4种手段准确定性,一级提取离子的峰面积定量.实验结果表明,15种邻苯二甲酸酯的质量偏差均小于3 ppm,在各自线性范围内线性关系良好,相关系数(r2)均大于0.996,检出限和定量下限分别为4.66～ 11.69 μg/kg和13.04 ～ 30.71 μg/kg,日内和日间精密度分别小于3.8％和6.7％,低、中、高3个加标水平的回收率为80.5％ ～108.3％,相对标准偏差(n=6)为0.4％～12.3％.在实际样品检测中,1例塑料玩具样品中检出邻苯二甲酸苄基丁基酯,含量为136.9μg/kg.该方法准确、高效、灵敏度高,可用于塑料玩具的实际检测.%An analytical method was developed for the rapid screening and quantitative detection of fifteen phthalates(PAEs) plasticizers in plastic toys by ultra-performance liquid chromatography-hybrid quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF MS).Plastic toy samples of different matrixes were extracted by a solvent dissolution-ultrasound extraction-precipitation seperation,cleaned up with a graphite carbon solid phase extraction column and concentrated by rotary evaporation and nitrogen blowing,then separated on a C18 column(2.1 mm ×50 mm,1.7 μm) by gradient elution,and detected in positive electrospray ionization (ESI +) and information dependent acquisition (IDA) MS/MS mode.The qualitative analyses for fifteen PAEs were performed by the synergic combination of the accurate m/z of TOF MS,isotopic distribution,retention time and library search results.The quantitative analyses were performed using the peak area of the extracted m/z of TOF MS.Experimental results demonstrated that a favorable mass accuracy less than 3 ppm was obtained for fifteen PAEs,and good linearities (r2 ＞ 0.996) were observed in the respective concentration ranges.The limits of detection(LODs) and limits of quantitation(LOQs) were in the ranges of 4.66-11.69 μg/kg and 13.04-30.71 μg/kg,with intra-day and inter-day(n =7) precision less than 3.8％ and 6.7％,respectively.The recoveries at three spiked levels ranged from 80.5％ to 108.3％,with relative standard deviations(RSDs,n =6) of 0.4％-12.3％.The present method was practically used to detect butyl benzyl phthalate in a plastic toy.This method was proved to be accurate,efficient and specific,and could be applied for the inspection of commercial plastic toys.