摘要
短链及中链氯化石蜡(SCCPs和MCCPs)因其持久性、生物毒性、富集性及长距离迁移等特点受到广泛关注。随着SCCPs和MCCPs在多种环境介质中的广泛检出,人类面临的暴露风险逐渐升高,因此开展人体内SCCPs和MCCPs的暴露评估具有重要意义。了解氯化石蜡(CPs)及其各同族体在血浆和血细胞中的分配行为及分布特征能够更好地掌握其在人体内的积累和循环情况,有助于准确、有效地评估CPs在人体内的暴露水平。本研究建立了Percoll不连续密度梯度离心方法,将人体血液分离为血浆、红细胞、白细胞和血小板4种组分,利用超声进行细胞破碎和提取,并采用多层硅胶柱去除脂质干扰。结果表明,使用80 mL正己烷-二氯甲烷(1∶1, v/v)和50 mL二氯甲烷作为样品净化的连续洗脱溶剂(合并收集)可实现血液样品中CPs与脂类大分子的选择性分离。采用气相色谱-电子捕获负化学源-低分辨质谱法(GC-ECNI-LRMS)测定人体血液不同组分中的SCCPs和MCCPs, SCCPs和MCCPs的方法检出限分别为1.57 ng/g湿重(n=7)和8.29 ng/g湿重(n=7),提取内标的回收率分别为67.0%~126.6%和69.5%~120.5%。采用该方法对采集的人体血液样品进行分析,所有样品中均有SCCPs和MCCPs检出,检出含量分别为10.81~65.23 ng/g湿重和31.82~105.65 ng/g湿重,其中红细胞中的SCCPs和MCCPs含量最高,其次是血浆,白细胞和血小板中的CPs含量相对较低。SCCPs和MCCPs在人体血液不同组分中的分布模式相似,SCCPs以C10-CPs为主,MCCPs以C14-CPs为主。该方法灵敏度高,操作便捷,能够满足人体血液样品的组分分离及各组分中SCCPs和MCCPs的定量分析需求。
Short⁃and medium⁃chain chlorinated paraffins(SCCPs and MCCPs)have attracted significant attention because of their persistence,biotoxicity,bioaccumulation,and long⁃range migration.Given their worldwide detection in a variety of environmental matrices,concerns re⁃lated to the high exposure risks of SCCPs and MCCPs to humans have grown.Thus,knowledge of the contamination patterns of SCCPs and MCCPs and their distribution characteristics in the vivo exposure of humans is of great importance.However,little information is available on the contamination of SCCPs and MCCPs in human blood/plasma/serum,mainly because of the dif⁃ficulty of sample preparation and quantitative analysis.In this study,a new blood sample pre⁃treatment method based on Percoll discontinuous density gradient centrifugation was developed to separate plasma,red blood cells,white blood cells,and platelets from human whole blood.A series of Percoll sodium chloride buffer solutions with mass concentrations of 1.095,1.077,and 1.060 g/mL were placed in a centrifuge tube from top to bottom to establish discontinuous density gradients.The dosage for each density gradient was 15 mL.Human whole blood sam⁃ples mixed with 085%sodium chloride aqueous solution were then added to the top layer of the Percoll sodium chloride solution.After centrifugation,the whole blood was separated into four components.The plasma was located at the top layer of the centrifuge tube,whereas the platelets,white blood cells,and red blood cells were retained at the junction of the various Percoll sodium chloride solutions.The sampling volume of human whole blood and incubation time were optimized,and results indicated that an excessively long incubation time could lead to hemolysis,resulting in a decrease in the recoveries of SCCPs and MCCPs.Therefore,a sam⁃pling volume of 1.5 mL and incubation time of 10 min at 4℃ were adopted.The cells of the blood components were further broken and extracted by ultrasonic pretreatment,followed by multilayer silica gel column chromatography for lipid removal.The use of 80 mL of n⁃hexane⁃dichloromethane(1∶1,v/v)and 50 mL of dichloromethane as the elution solvents(collected together)for the gel column separated the SCCPs and MCCPs from the lipid molecules in the blood samples.Gas chromatography⁃electron capture negative ion⁃low resolution mass spec⁃trometry(GC⁃ECNI⁃LRMS)was used to determine the SCCPs and MCCPs.Quantification using the corrected total response factor with degrees of chlorination was achieved with linear correc⁃tions(R^(2)=0.912 and 0.929 for the SCCPs and MCCPs,respectively).The method detection limits(MDLs)for the SCCPs and MCCPs were 1.57 and 8.29 ng/g wet weight(ww,n=7),respectively.The extraction internal standard recoveries were 67.0%-126.6%for the SCCPs and 69.5%-120.5%for the MCCPs.The developed method was applied to determine SCCPs and MCCPs in actual human whole blood samples.The contents of SCCPs and MCCPs were 10.81-65.23 and 31.82-105.65 ng/g(ww),respectively.Red blood cells exhibited the highest contents of CPs,followed by plasma,white blood cells,and platelets.The proportions of SCCPs and MCCPs in red blood cells and plasma were 70%and 66%,respectively.In all four components,the MCCP contents were higher than the SCCP contents,and the ratios of MCCPs to SCCPs ranged from 1.04 to 3.78.Similar congener patterns of SCCPs and MCCPs were found in the four components of human whole blood.C10⁃CPs and C14⁃CPs were predominantly ob⁃served in the SCCPs and MCCPs,respectively.In summary,a simple and efficient method was proposed to determine low concentrations of SCCPs and MCCPs in human blood with high sensitivity and selectivity.This method can meet requirements for the quantitative analysis of SCCPs and MCCPs in human blood components,thereby providing technical support for human health risk assessment.
作者
于霜
高媛
朱秀华
耿柠波
代玉冰
洪建尧
陈吉平
YU Shuang;GAO Yuan;ZHU Xiuhua;GENG Ningbo;DAI Yubing;HONG Jianyao;CHEN Jiping(CAS Key Laboratory of Separation Science for Analytical Chemistry,Dalian Institute of Chemical Physics,Dalian 116023,China;School of Environmental and Chemical Engineering,Dalian Jiaotong University,Dalian 116028,China)
出处
《色谱》
CAS
CSCD
北大核心
2023年第8期698-706,共9页
Chinese Journal of Chromatography
基金
国家自然科学基金(21976174,22276186)
辽宁省自然科学基金(2020-MS-023)。
关键词
气相色谱-电子捕获负化学源-低分辨质谱法
短链氯化石蜡
中链氯化石蜡
样品提取与净化
人体血液
gas chromatography⁃electron capture negative ion⁃low resolution mass spectrome⁃try(GC⁃ECNI⁃LRMS)
short⁃chain chlorinated paraffins(SCCPs)
medium⁃chain chlorinated paraffins(MCCPs)
sample extraction and purification
human blood
