Department of Chemistry and Industrial Chemistry, University of Genoa, Via Dodecaneso 31, 16146 Genoa, Italy.
Talanta. 2011 Oct 15;85(5):2375-84. doi: 10.1016/j.talanta.2011.07.085. Epub 2011 Aug 11.
Fast liquid chromatography coupled to triple-quadrupole tandem mass spectrometry was employed for the determination of six UV filters in seawater. The separation of the analytes was achieved in less than 5 min; polarity switching was used as four of the analytes were ionized in positive mode and the remaining two in negative mode. Two ionization sources were employed and compared: atmospheric pressure chemical ionization (APCI) gave better results than electrospray ionization (ESI) for all analytes, with higher reproducibility and lower detection limits. Therefore APCI was chosen for the determination of the analytes in seawater samples using stir bar sorptive extraction-liquid desorption (SBSE-LD). Quantitative analysis was performed in multiple reaction monitoring (MRM) mode; fragmentation pathways of the analytes with regard to the formation of the MRM ions were also proposed. For the analysis of seawater samples, calibration curves were drawn using SBSE in spiked seawater. All figures of merit of the method were satisfactory; limits of detection were particularly low for the four analytes ionized in positive mode, being in the range 8-31 ng/L. The method was applied to the determination of the six UV filters in seawater samples from Liguria, Italy. Only benzophenone-3 (BP-3) and ethylhexyl methoxycinnamate (EHMC) were measured in the analyzed samples; some of the remaining analytes were also detected but always below the limit of quantitation.
采用快速液相色谱-三重四极杆串联质谱法测定海水中的六种紫外线滤光剂。在不到 5 分钟的时间内实现了分析物的分离；采用极性切换，因为其中四种分析物在正模式下电离，其余两种在负模式下电离。使用了两种离子源进行比较：大气压化学电离（APCI）比电喷雾电离（ESI）对所有分析物都能产生更好的结果，具有更高的重现性和更低的检测限。因此，APCI 被选为搅拌棒吸附萃取-液解吸（SBSE-LD）测定海水中分析物的方法。采用多反应监测（MRM）模式进行定量分析；还提出了分析物形成 MRM 离子的碎裂途径。对于海水样品的分析，使用 SBSE 在加标海水中绘制校准曲线。该方法的所有衡量标准都令人满意；对于在正模式下电离的四种分析物，检测限特别低，范围为 8-31 ng/L。该方法应用于测定意大利利古里亚地区海水中的六种紫外线滤光剂。在分析样品中仅检测到二苯甲酮-3（BP-3）和乙基己基甲氧基肉桂酸（EHMC）；其余一些分析物也被检测到，但始终低于定量限。
