饮用水中16种双酚类化合物的在线固相萃取超高效液相色谱串联质谱法测定方法研究

Determination of 16 bisphenols in drinking water by online solid-phase extraction-ultra highperformance liquid chromatography tandem mass spectrometry

[背景]双酚类化合物(BPs)属于非持久性环境内分泌干扰物,在饮用水中检出率高,存在饮水途径摄入风险。[目的]为了高效开展饮用水中BPs的监测工作,建立并优化了同时测定饮用水中16种BPs的在线固相萃取-超高效液相色谱-三重四级杆质谱检测方法。[方法]比较在线固相萃取(SPE)条件,以及不同色谱柱、流动相体系、质谱参数等条件对BPs色谱峰的影响,优化了水样保存和前处理过程等处理条件。饮用水样品调节pH和去除固体颗粒,经在线SPE系统提取净化后,超高效液相色谱-串联质谱法检测,同位素内标法定量。以纯水和管网末梢水为基质开展方法学验证实验。加标回收率评估方法的准确度,相对标准偏差评价方法的精密度,并采集不同区域的88件管网末梢水样本进行方法应用。[结果]16种BPs待测物在1~75 ng·L^(-1)浓度范围内线性良好,相关系数均大于0.995。方法检出限低于0.30 ng·L^(-1),方法定量限低于1.0 ng·L^(-1)。16种BPs待测物的加标质量浓度为5.0、15、40 ng·L^(-1)时,待测物的平均加标回收率在(100±10)%之间,相对标准偏差均小于10%。同时,使用本方法对88件管网末梢水样品进行定量检测。相关样品中可检出多种BPs,双酚S(BPS)、双酚A(BPA)和双酚AF(BPAF)检出率较高,分别达到93.2%、77.3%和29.5%,其中BPS检测浓度为未检出(N.D.)~37.8 ng·L^(-1),BPA检测浓度为N.D.~52.0 ng·L^(-1)。[结论]本方法中使用在线固相萃取系统,前处理方法简便,样品用量少,自动化程度高。方法检出限低,准确度和精密度良好。本方法实用性强,可应用于饮用水中ng·L^(-1)浓度级别的16种BPs的定量监测。

[Background]Bisphenol compounds are non-persistent environmental endocrine disruptors and frequently detected in drinking water systems,indicating potential human health risks through drinking water.[Objective]To establish and optimize a simultaneous determination method for 16 BPs in drinking water by online solid-phase extraction-ultra high-performance liquid chromatography-triple quadrupole mass spectrometry,in order to efficiently monitoring BPs in drinking water.[Methods]Candidate online solid-phase extraction conditions,chromatographic columns,mobile phase systems,mass spectrometry parameters,and other conditions were compared by chromatographic peaks of BPs,and processing conditions such as water sample preservation and pretreatment were optimized.The pH level of drinking water samples was adjusted and solid particles were removed.After extraction and purification by an online solid-phase extraction system,samples were detected by ultra-high performance liquid chromatography tandem mass spectrometry and quantified by isotope internal standard method.The proposed method was verified by pure water and terminal tap water,and evaluated by spiked recovery rate and relative standard deviation.Eighty-eight tap water samples from different regions of local pipeline network were collected for method application.[Results]For the 16 BPs,the calibration curves showed good linearity between 1.0 and 75 ng·L^(-1)and the correlation coefficients were greater than 0.995.The detection limit of the method was less than 0.30 ng·L^(-1),and the quantification limit of the method was less than 1.0 ng·L^(-1).When the spiked concentrations for the 16 BPs were 5.0,15,and 40 ng·L^(-1),the average spiked recovery rates of the test substances were between(100±10)%,and the relative standard deviations were all below 10%.In the method application to the local terminal water samples,the positive rates of bisphenol S(BPS),bisphenol A(BPA),and bisphenol AF(BPAF)were as high as 93.2%,77.3%,and 29.5%,respectively.The concentrations of BPS were from not detected(N.D.)to 37.8 ng·L^(-1),and the concentrations of BPA were from N.D.to 52.0 ng·L^(-1).[Conclusion]The method using an online solid-phase extraction system is established,featuring simple pre-treatment,small sample volume,high degree of automation,low detection limit,and good accuracy and precision.This method can be applied to the quantitative monitoring of 16 BPs at ng·L^(-1)level in drinking water.