This study describes several original methods that were developed with the goal of measuring phthalates and terephthalates. These methods include gas chromatography/mass spectrometry (GC/MS), GC/MS/MS, liquid chromatography with UV detection (LC/UV), LC/MS, and LC/MS/MS. The study compares the advantages and disadvantages of these methods and their applicability to measuring phthalates and terephthalates in the liquids used in electronic cigarettes (e-liquids). The analytes evaluated include eight phthalates and two terephthalates. The phthalates were diethyl, dibutyl, benzyl butyl, diphenyl, bis(2-ethylhexyl), di-n-octyl, diisononyl and diisodecyl. The terephthalates were dimethyl and bis(2-ethylhexyl). Intentionally, no cleanup or concentration step were used in the methods. The methods used two chromatographic standards, dimethyl phthalate-3,4,5,6-d₄, and di-(2-ethylhexyl) phthalate-3,4,5,6-d₄. All techniques were validated for selectivity/specificity, precision, sensitivity (evaluation of LOD and LOQ), as well as for repeatability and matrix interference. The GC methods were not adequate for the analysis of diphenyl, diisononyl, and diisodecyl phthalates which were not volatile enough to be seen in the conditions used for the GC separation. Also, alcohols should not be used as solvents for the injection of the sample in the GC system to avoid transesterification in the hot injection port. The single quadrupole MS detection in GC offers sensitivities around 1 μg/mL in the e-liquid and was not sensitive enough for the analysis of trace phthalates and terephthalates. Compared to all evaluated methods, the MS/MS detection in GC offered the best sensitivity (below 10 ng/mL in the e-liquid). The LC is adequate for the separation of all the evaluated analytes. However, the UV detection in LC does not offer good sensitivity compared to all the other techniques. The MS detection in LC provides poor sensitivity for terephthalates, but better than the UV for the rest of the analytes. The MS/MS detection for LC offers slightly better sensitivity than the MS detection, but both LC/MS and LC/MS/MS were only able to measure levels above about 100 ng/mL of analytes in the e-liquid. A group of 39 e-liquids were analyzed by three of the evaluated procedures. Benzyl butyl phthalate, bis(2-ethylhexyl) terephthalate, and di-n-octyl phthalate were not detected in the e-liquids. Some of the other evaluated phthalates were present at trace levels in certain e-liquids while most e-liquids did not contain phthalates at detectable levels.

这项研究描述了几种旨在测量邻苯二甲酸盐和对苯二甲酸盐的原始方法。这些方法包括气相色谱/质谱（GC / MS），GC / MS / MS，带有UV检测的液相色谱（LC / UV），LC / MS和LC / MS / MS。该研究比较了这些方法的优缺点，以及它们在测量电子烟所用液体（电子液体）中邻苯二甲酸盐和对苯二甲酸盐时的适用性。评估的分析物包括八种邻苯二甲酸酯和两种对苯二甲酸酯。邻苯二甲酸酯是二乙基，二丁基，苄基丁基，二苯基，双（2-乙基己基），二正丁基-辛基，二异壬基和二异癸基。对苯二甲酸酯是二甲基和双（2-乙基己基）。故意地，在这些方法中没有使用净化或浓缩步骤。该方法使用两种色谱标准品，邻苯二甲酸二甲酯-3,4,5,6-d ₄和邻苯二甲酸二-（2-乙基己基）酯-3,4,5,6-d ₄。验证了所有技术的选择性/特异性，精密度，灵敏度（LOD和LOQ的评估）以及可重复性和基质干扰。GC方法不足以分析邻苯二甲酸二苯酯，二异壬基酯和邻苯二甲酸二异癸酯，因为它们的挥发性不足以在用于GC分离的条件下观察到。同样，在GC系统中，不应将醇用作进样的溶剂，以避免在热进样口中发生酯交换反应。GC中的单四极杆质谱检测器在电子液体中的灵敏度约为1μg/ mL，并且对痕量邻苯二甲酸盐和对苯二甲酸盐的分析不够灵敏。与所有评估方法相比，GC中的MS / MS检测提供了最佳的灵敏度（电子液体中的浓度低于10 ng / mL）。液相色谱足以分离所有评估的分析物。但是，与所有其他技术相比，LC中的UV检测不能提供良好的灵敏度。LC中的MS检测对对苯二甲酸酯的灵敏度较差，但对其余分析物的紫外检测灵敏度却优于UV。LC的MS / MS检测提供的灵敏度比MS检测稍好，但是LC / MS和LC / MS / MS只能测量电子液体中分析物的含量约100 ng / mL以上。通过三种评估程序对一组39种电子液体进行了分析。邻苯二甲酸苄基丁酯，对苯二甲酸双（2-乙基己基）酯和 但对于其余的分析物而言，它比紫外线更好。LC的MS / MS检测提供的灵敏度比MS检测稍好，但是LC / MS和LC / MS / MS只能测量电子液体中分析物的含量约100 ng / mL以上。通过三种评估程序对一组39种电子液体进行了分析。邻苯二甲酸苄基丁酯，对苯二甲酸双（2-乙基己基）酯和 但对于其余的分析物而言，它比紫外线更好。LC的MS / MS检测提供的灵敏度比MS检测稍好，但是LC / MS和LC / MS / MS只能测量电子液体中分析物的含量约100 ng / mL以上。通过三种评估程序对一组39种电子液体进行了分析。邻苯二甲酸苄基丁酯，对苯二甲酸双（2-乙基己基）酯和在电子液体中未检测到邻苯二甲酸正辛酯。其他某些评估的邻苯二甲酸盐在某些电子液体中以痕量水平存在，而大多数电子液体不含可检测水平的邻苯二甲酸盐。