十八烷基离子液体杂化固相微萃取整体柱用于检测咖啡中的多环芳烃

Application of Octadecyl Ionic Liquid Hybrid Solid-phase Microextraction Monolithic Column in the Detection of Polycyclic Aromatic Hydrocarbons in Coffee

以自制的1-十八烷基-3-(γ-三乙氧基硅基丙基)咪唑溴盐离子液体(C18IL)、二苯基二甲氧基硅烷(DDS)和四乙氧基硅烷(TEOS)为功能单体,采用溶胶-凝胶法制备了烷基咪唑基离子液体管内固相微萃取整体柱(C18IL in-tube SPME).以多环芳烃为分析对象,考察了C_(18)IL含量对C_(18)IL in-tube SPME萃取性能的影响,并对萃取条件进行了优化.建立了基于C_(18)IL in-tube SPME-气相色谱(GC-FID)的分析方法,用于检测萘、芴、菲、荧蒽和芘5种多环芳烃.该方法的检出限(S/N=3)为0.007~0.072μg/L,定量限(S/N=10)为0.023~0.24μg/L,日内和日间精密度(RSD)除菲类多环芳烃外均小于10%.将该方法用于检测咖啡中5种多环芳烃,3个不同浓度下的加标回收率为85.79%~103.42%.

Ionic liquid of 1-octadecyl-3-（γ-triethoxysiliconpropyl）imidazole bromide（ClslL） was synthesized and then used as a functional monomer to produce the in-tube solid microextraction monolithic column（ C18 IL in-tube SPME） via sol-gel reaction. After that, five polycyclic aromatic hydrocarbons （PAHs）, naphthalene, fluorine, phenanthrene, fluoranthene and pyrene, were employed as probe analytes to evaluate the preparation method of the column and optimize the extraction conditions. Finally, a method of C18 IL in-tube SPME hyphen gas chromatography was established for the determination of PAHs in water. The limits of detection （LODs, S/N = 3） were between 0.007 and 0.072 μg/L, and the limits of quantification（ LOQs, S/N = 10） varied from 0.023 to 0.24 μg/L. The intra- and inter-day relative standard deviations （RSDs） of the PAHs were below 10% except for that of phenanthrene. The proposed method was also applied to the determination of the PAHs in a coffee sample, and the recoveries for the five PHAs（spiked in the coffee sample at three levels） ranged from 85.79% to 103.42%.