氧化石墨烯接枝硅胶整体柱制备及在多环芳烃检测中的应用

Preparation of Graphene Oxide Grafted Silica Monolith and Application in Determination of Polycyclic Aromatic Hydrocarbons

多环芳烃(Polycyclic aromatic hydrocarbons, PAHs)是优先控制环境污染物。本研究通过酰胺化反应将氧化石墨烯(Graphene Oxide,GO)接枝到自制的氨基化硅胶整体柱表面,制得GO接枝硅胶整体柱,利用扫描电镜、元素分析和拉曼光谱对其进行表征分析。以此为固相微萃取柱,在优化的实验条件下,考察了其对典型PAHs的萃取富集性能。整体柱对芘(Pyr)、苯并[a]芘(BaP)和二苯并[a,h]蒽(DahA)的富集倍数分别达到了78.5、98.2和102.4,GO与PAHs之间的π-π堆积作用和疏水作用使整体柱对典型PAHs表现出较强的富集能力。结合高效液相色谱-紫外检测装置建立了PAHs定量方法,检出限(S/N=3)为0.02～0.11μg/L,定量限(S/N=10)为0.07～0.36μg/L,9种PAHs在0.1～150μg/L的浓度范围内线性关系良好(R^2≥0. 9947)。香烟烟气、焦化厂废水、大气颗粒物等实际样品中PAHs加标回收率为81.5%～107.8%,相对标准偏差为1.0%～6.5%(n=3)。本方法准确灵敏、简便可靠,可用于实际样品PAHs的检测。

Being priority control environmental pollutants, the determination of polycyclic aromatic hydrocarbons(PAHs) is of great significance. In this work, a novel silica monolith was prepared by grafting graphene oxide(GO) onto the surface of silica monolith through amidation reaction. The morphology and structure of the monolith were characterized by scanning electron microscopy, elemental analysis and Raman spectroscopy. Using this monolith as a solid phase microextraction(SPME) medium, the extraction performances for typical PAHs were extensively investigated. The enrichment factors of the monolith for Pyrene(Pyr), Benzo [a] pyrene(BaP) and dibenzo [a, h] anthracene(DahA) were 78.5, 98.2 and 102.4, respectively. The excellent enrichment property of the monolith for PAHs was attributed to the π-π stacking and hydrophobic interactions between GO and PAHs. Therefore, a facile and sensitive detection method for PAHs was developed coupled with high performance liquid chromatography-ultraviolet(HPLC-UV). The linear range was 0.1-150 μg/L for nine PAHs(R^2≥0. 9947), with limits of detection(LOD) and limits of quantification(LOQ) of 0.02-0.11 μg/L(S/N = 3) and 0.07-0.36 μg/L(S/N=10), respectively. The spiked recoveries of PAHs in cigarette smoke, coke waste water and local atmospheric particles were between 81.5% and 107.8%, with the relative standard deviations(RSDs) from 1.0% to 6.5%(n=3). Furthermore, the developed method was accurate, sensitive, simple and reliable, and had great potential applicability in determination of real samples.