以四氯化镉酸根离子[CdCl4]2-诱导形成的Eu3+-七元瓜环(Q[7]/Eu)多维配位聚合物为涂层材料,采用高温环氧树脂固定涂层制备了一种新型固相微萃取纤维。利用电镜和热重分析对纤维的表面形态和热稳定性进行了考察。实验结果表明该聚合物涂层表面疏松、多孔,热稳定性好。在优化的实验条件下(萃取温度75℃,NaCl质量浓度为200 g/L,萃取时间40 min,250℃下解吸2 min)结合GC/FID的方法测定了水样中萘、苊、芴、菲、蒽、荧蒽、芘7种多环芳烃(PAHs)化合物。7种PAHs的线性范围为1~1 000μg/L,检出限在0.29~2.09μg/L之间,相对标准偏差(RSD,n=5)不大于8.6%。将建立的方法用于实际样品花溪河水中PAHs加标回收率的测定,回收率在97.2%~109.0%之间,结果令人满意。在各自的最优萃取条件下,该涂层对7种PAHs的萃取效果与商品PDMS的萃取效果相当,证明该Q[7]/Eu多维配位聚合物在固相微萃取方面具有应用潜力。
A novel solid-phase microextraction fiber was prepared via simple adhesion process.Fused silica fiber was used as supporting substrate and the cucurbit[7]uril / Eu coordination polymers induced by [CdCl4]2-anion was affixed onto the surface of fused silica fiber with high temperature epoxy resin as a sorbent coating. The SPME coating was characterized by scanning electron microscopy and thermal analysis. Coupled to gas chromatography,the fiber was used to extract polycyclic aromatic hydrocarbons(PAHs)in aqueous samples. Analytical performances of the proposed method were investigated under the optimum extraction condi tions(extraction temperature,75 ℃;mass concentration of NaCl,200 g / L;extraction time,40 min;desorption time,2 min;desorption temperature,250 ℃)compared with commercial fibers for the same analytes. For the seven PAHs(naphthalene,acenaphthene,fluorene,phe nanthrene,anthracene,fluoranthene and pyrene),good linearity was obtained ranging from 1μg / L to 1 000 μg / L. Limits of detection were 0. 29- 2.09 μg / L with the RSDs no more than8. 6%. The established SPME GC method was applied to determine the spiked PAHs in real riv er water samples and satisfactory results were obtained with recoveries between 97. 2% and109. 0%. Under the optimal conditions,the extraction effect of home made coating was similar to the commercial PDMS(polydimethylsiloxane)coating,which further confirmed its potentialin the solid-phase microextraction.