1-丁基-3-甲基咪唑六氟磷酸盐离子液体对PEG20M固相微萃取涂层萃取性能的影响

Effect of Ionic Liquid 1-butyl-3-Methyl Imidazole Hexafluorophosphorate on the Extraction Performance of PEG20M Solid Phase Microextraction Coating

利用1-丁基-3-甲基咪唑六氟磷酸盐离子液体和PEG20M为涂层材料,制备了复合PEG20M固相微萃取探头,与气相色谱联用测定了水中邻氯苯酚和4-硝基甲苯,并对萃取温度、萃取时间、盐浓度、溶液p H值等萃取条件,解吸温度和解吸时间进行了优化,结果表明:当水样中氯化钠浓度为0.40 g/m L,p H=5时,于30℃萃取30 min,萃取效果最好;140℃下3 min可完成解吸.与未加离子液体的PEG20M固相微萃取涂层相比,该涂层改善了检测的检出限和重现性,但因离子液体粘度较大等,涂层制备的重现性有待进一步提高.

A composite PEG20 M solid-phase micro-extraction（ SPME） fiber was prepared using 1-butyl-3-methyl imidazole hexafluorophosphorate（ a typical ionic liquid） and PEG20 M as the coating materials. o-chlorophenol and 4-nitrotoluene in water were determined using the fiber in headspace SPME（ HS-SPME） mode coupled with gas chromatography. The extraction conditions（ temperature,time,salinity,p H value）,desorption temperature and desorption time were optimized.The results indicated that the best effect colud be obtained when extraction was carried out in the medium modified by Na Cl（ ρNa Cl= 0. 40 g / m L,p H = 5） at 30 ℃ for 30 minutes. Desorption can be finished in 3 minutes at 140 ℃. Compared with PEG20 M SPME fiber without ionic liquid,the composite coating improved the detection limit and reproducibility.However,the reproducibility of fiber preparation should be improved due to the high viscosity of the ionic liquid.