色谱2024，Vol.42Issue(11)：1042-1051,10.DOI:10.3724/SP.J.1123.2024.01005
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 framework composite aerogel
摘要
Abstract
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-dichlorophenoxyace-tic acid is 30 μg/L in China's standards for drinking water quality,70 μg/L in the United States'drinking water standards,and 30 μg/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 aer-ogels exhibit a hierarchical porous structure,which enhances the affinity and mass transfer effi-ciency 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 aerogel was then used for the dispersive solid phase extraction(DSPE)of seven PCAs from environmental water,followed by ultra-high per-formance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS).The key param-eters affecting the efficiency of DSPE,including the extraction conditions,ratio of MIL-101(Fe)-NH2 to sodium alginate,pH of the aqueous samples,extraction time,ionic strength(sa-linity),and elution conditions,such as the elution solvent ratio,elution time,and elution vol-ume,were investigated to obtain optimal extraction efficiency.The adsorbent could adsorb the target contaminants within 12 min,and the analytes could be completely desorbed within 30 s by elution with 4 mL of 1.5％(v/v)formic acid in methanol solution.The water samples could be analyzed without pH adjustment.The main adsorption mechanisms were electrostatic inter-actions and π-π conjugation.Thus,a new method based on MOF aerogels coupled with UH-PLC-MS/MS was developed for the determination of the seven PCA residues in water.The cali-bration curves for the seven PCAs showed good linearity(r2 ≥0.998 6),with limits of detection(LODs)and quantification(LOQs)ranging from 0.30 to 1.52 ng/L and from 1.00 to 5.00 ng/L,respectively.Good intra-and inter-day precision values of 6.5％-17.1％and 7.4％-19.4％,respectively,were achieved under low(8 ng/L),medium(80 ng/L),and high(800 ng/L)spiking levels.The developed method was applied to the detection of PCAs in surface water,seawater,and waste leachate,and the detected mass concentrations ranged from 0.6 to 19.3 ng/L.Spiked recovery experiments were conducted at mass concentrations of 8,80,and 800 ng/L,and the recoveries ranged from 61.7％to 120.3％.The proposed method demon-strates good sensitivity,precision,and accuracy,and has potential applications in the detection of trace PCAs in environmental water.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Key words
ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)/dispersive solid phase extraction(DSPE)/composite aerogel/metal-organic frame-works/phenoxy carboxylic acid herbicide/environmental waters分类
化学化工引用本文复制引用
张鑫,吴阁格,崔文连,李爽,马继平..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[J].色谱,2024,42(11):1042-1051,10.基金项目
国家自然科学基金项目(21976099).National Natural Science Foundation of China(No.21976099). （21976099）
