氨基化共价有机骨架固相微萃取涂层用于水体中酚类的高效萃取

An Amino-functionalized Covalent Organic Framework Coating for Highly Efficient Solid Phase Microextraction of Trace Phenols in Water

酚类化合物是一类常见的环境污染物,由于浓度低、极性较强且样品基质复杂,对其分析检测前需采用样品前处理技术以进行有效地分离和富集。固相微萃取(SPME)是一种集采样、富集、进样于一体的无溶剂前处理技术,与气相色谱-质谱(GC-MS)等联用可实现复杂基质中痕量有机物的快速富集和检测。本文采用无溶剂合成策略,一步合成了氨基改性的共价有机骨架(COFs)材料(TpPa-NH2),合成方法简单绿色,无需溶剂。将其制备成SPME涂层,以5种酚类化合物作为目标分析物,基于顶空模式进行萃取,结合GC-MS作为检测手段,建立了SPME-GC-MS检测酚类化合物的新方法。与未氨基改性的TpPa-1涂层相比,TpPa-NH2萃取酚类化合物的性能是其3~5倍,表明氨基官能团可有效地提高萃取酚类化合物的性能。在最佳条件下,该方法线性范围为10~5.0×10^(4)ng/L,线性相关系数为0.996~0.999,检出限为1.30~5.35ng/L。涂层批内的相对标准偏差(RSD)在4.2%~8.9%之间,批间的RSD在2.6%~8.2%之间,且该涂层可以重复使用90次以上。基于TpPa-NH2涂层材料建立的SPME-GC-MS检测酚类化合物的分析方法,已成功应用于环境水样标准物质中酚类化合物的检测。

BACKGROUND:Phenolic compounds,as ubiquitous pollutants,should be effectively separated by sample pretreatment technology prior to analysis because of the low concentration,strong polarity and complex sample matrix.Solid phase microextraction(SPME)is a solvent-free pretreatment technology integrating sampling,enrichment and injection.Combined with gas chromatography-mass spectrometry(GC-MS),it can achieve the rapid enrichment and detection of trace organic compounds in a complex matrix.OBJECTIVES:To develop a sensitive,simple,and environmentally friendly method for the determination of trace phenols.METHODS:An amino functionalized covalent organic framework(TpPa-NH2)was synthesized by a solvent-free method in one step.SPME was used as the coating,four kinds of phenolic compounds were used as target analytes,and a new method for the detection of phenolic compounds was established by headspace extraction mode combined with GC-MS.RESULTS:The extraction performance of TpPa-NH2was 3-5 times that of TpPa-1.Under the optimum conditions,the established analysis method for four phenols had wide linear ranges(10-5.0×10^(4)ng/L),high linear correlation coefficients(0.996-0.999),and low detection limits(1.30-5.35 ng/L).Both the intra-fiber repeatability(RSD from 2.2%-9.2%)and inter-fiber reproducibility(RSD from 4.2%-8.9%)were satisfactory,and the coating can be reused more than 90 times.CONCLUSIONS:The introduction of an amino group can effectively improve the extraction performance of TpPa for phenolic compounds.The established method establishes the sensitive,convenient and green detection of phenolic compounds in actual samples,demonstrating a good application prospect.