基于金属有机骨架材料复合气凝胶的分散固相萃取-超高效液相色谱-串联质谱法测定水中7种苯氧羧酸类除草剂  

Determination of seven phenoxy carboxylic acid herbicides in water using dispersive solid phase extraction coupled with ultra-high performance liquid chromatography-tandem mass spectrometry based on metal-organic

作　　者：张鑫 吴阁格 崔文连 李爽 马继平[1] ZHANG Xin;WU Gege;CUI Wenlian;LI Shuang;MA Jiping(College of Environmental and Municipal Engineering,Qingdao University of Technology,Qingdao 266000,China;Qingdao Ecological Environment Monitoring Center of Shandong Province,Qingdao 266000,China)

机构地区：[1]青岛理工大学环境与市政工程学院,山东青岛266000 [2]山东省青岛生态环境监测中心,山东青岛266000

出　　处：《色谱》2024年第11期1042-1051,共10页Chinese Journal of Chromatography

基　　金：国家自然科学基金项目(21976099).

摘　　要：苯氧羧酸类除草剂(PCAs)在水体中难以降解,对人类健康和生态环境造成严重威胁,因此亟需建立有效测定水体中痕量PCAs的方法。本文以常温干燥法制备的金属有机骨架/海藻酸钠气凝胶材料MIL-101(Fe)-NH 2/SA作为分散固相萃取的吸附剂,对环境水体中的7种PCAs进行吸附和富集,从萃取条件(气凝胶中MIL-101(Fe)-NH 2与海藻酸钠比例、水样pH、萃取时间)、洗脱条件(洗脱溶剂比例、洗脱时间、洗脱体积)、离子强度(盐度)等方面对萃取效果进行优化,以获得最佳的萃取效果。优化结果显示,吸附剂在12 min内可以对目标物进行完全吸附,用总体积为4 mL的含1.5%甲酸的甲醇洗脱30 s,目标物可以充分解吸。在最优条件下,结合超高效液相色谱-串联质谱法(UHPLC-MS/MS),建立了基于金属有机骨架复合气凝胶测定水体中7种PCAs的新方法。该方法可以呈现良好的线性关系(r^(2)≥0.9986),检出限和定量限分别为0.30~1.52 ng/L和1.00~5.00 ng/L。在低(8 ng/L)、中(80 ng/L)、高(800 ng/L)3个水平下进行精密度试验,日内和日间精密度(以RSD计)分别为6.5%~17.1%和7.4%~19.4%。该方法应用于地表水、海水、垃圾渗滤液的检测中,检出量为0.6~19.3 ng/L;在8、80、800 ng/L 3个水平下进行加标回收试验,回收率为61.7%~120.3%。该方法具有良好的灵敏度、精密度和准确度,为环境水体中苯氧羧酸类物质的痕量检测提供了一种新的检测方法。Phenoxy carboxylic acid herbicides(PCAs)are difficult to degrade and,thus,pose significant threats to the environment and human health.The limit for^(2),4-dichlorophenoxyacetic acid is 30μg/L in China’s standards for drinking water quality,70μg/L in the United States’drinking water standards,and 30μg/L in the World Health Organization’s guidelines for drinking water quality.Therefore,the development of an effective detection method for trace PCAs in water is a crucial endeavor.Metal-organic frameworks(MOFs)are novel porous materials that possess advantages such as a large specific surface area,adjustable pore size,and abundant active sites.They exhibit excellent adsorption capability for various compounds.However,the applications of MOFs as adsorbents are limited.For example,the process of isolating powdered MOFs from aqueous solutions is laborious,and microporous MOFs exhibit limited surface affinity,which decreases their mass transfer efficiency in the liquid phase.MOF crystals can be embedded in a substrate to overcome these limitations.Aerogels are obtained by drying hydrogels,which are hydrophilic polymers with a three-dimensional crosslinked network structure.Spongy aerogel materials exhibit unique structural properties such as high porosity,large pore volume,ultralow density,and easy tailorability.When MOFs are combined with an aerogel,their efficient and selective adsorption properties are preserved.In addition,MOF aerogels exhibit a hierarchical porous structure,which enhances the affinity and mass transfer efficiency of the MOF for target molecules.At present,MOF aerogels are primarily prepared by freeze-drying or using supercritical carbon dioxide.These drying processes require significant amounts of energy and time.Hence,the development of greener and more efficient methods to prepare skeleton aerogels is urgently needed.In this study,we prepared an environment-friendly aerogel at ambient temperature and pressure without the use of specialized drying equipment.This ambient-dried MOF composite

关 键 词：超高效液相色谱-串联质谱 分散固相萃取 复合气凝胶 金属有机骨架材料 苯氧羧酸除草剂 环境水体 

分 类 号：O658[理学—分析化学]