A stainless steel wire was immersed in a hydrophobic ionic liquid (IL, i.e. 1-octyl-3-methylimidazolium hexafluorophosphate), then was heated under an infrared lighter to make the viscous IL form an even and reproducible film on the steel wire. After that polyaniline (PANI) was electrodeposited on it from an aqueous solution containing 0.1 mol.L-1 aniline and 1.0 moloL-1 HNO3 through cyclic voltammetry. The potential range was --0.2~1.2 V (vs. saturated calomel electrode, SCE), the scan rate was 50 mVos 1 and the cyclic potential scan was repeated for 70 times. For the electrodeposi- tion a conventional three-electrode system was adopted, including the IL coated stainless steel wire as working electrode, a platinum wire as counter electrode and a saturated calomel electrode as reference electrode. The resulting PANI-IL composite coating was rinsed with methanol and distilled water. Following this, it was conditioned in a electric furnace with nitrogen atmosphere at 90 ~C for 30 min, at 250 ~C for 150 min. When the obtained fiber was cool, it was fixed on a home-made device for solid-phase microextraction (SPME) with epoxy resin. The coating showed netlike structure, with smaller hole and larger surface area than that of PANI. Taking several phenolic derivatives (i.e. 2-chlorophenol, 2-methylphenol, 2,6-dimethylphenol, 2,4-dimethylphenol and 3-methylphenol) as models, the analytical performance of the fiber was investi- gated. Under the optimized conditions (i.e. extraction temperature: 60 ~C; extraction time: 40 min; stirring rate: 600 r/min; NaCI concentration: 0.35 gomL-l; desorption time: 3 min; desorption temperature: 250 ~C), when the phenols were deter- mined by GC after headspace solid-phase microextraction with the fiber, the linear ranges were 0.048~400 gg.L-~ with correlation coefficients above 0.99; the detection limits were 6.1~98 ng~L-~ (S/N=3). The relative standard deviations (RSD) of chromatographic peak area were smaller than 5.5% for five successive measurements with single fiber, and the fiber to fiber RSD was 3.7%~12% for different phenols (n=3). The fiber also presented good stability and its extraction efficiency kept almost unchanged after being used for about 150 times; when the temperature was up to 300 ~C it did not decompose. In comparison with PANI fiber, the PANI-IL fiber showed higher extraction capability. The PANI-IL fiber was successfully applied to the determination of phenols in waste water from a chemical factory.%在0．1mol·L-1苯胺＋1．0mol·L-1 HNO3水溶液中，通过循环伏安法在涂有疏水性离子液体1-辛基-3-甲基咪唑一六氟磷酸盐的不锈钢丝上制备了新型离子液体一聚苯胺（IL—PANI）复合萃取涂层．制得的IL—PANI涂层呈网状结构，比表面积比PANI大，IL则分散在PANI表面和网孔内．以几种苯酚衍生物为目标分析物，对所得萃取头的性能进行了考察．在优化后的实验条件下，对这些酚类化合物进行顶空固相微萃取-气相色谱检测，其线性范围为0．048-400μg·L-1，检出限为6．1～98ng·L-1（S／Y=3）．同一萃取头萃取五次的相对标准偏差（RSD）d,于5．5％；多根萃取头平行萃取的RSD为3．7％～12％fM=3）．PANI-IL涂层有良好的稳定性，在使用150多次后萃取性能仅有很小的变化；在温度高至300℃时不分解．与聚苯胺涂层相比，其萃取效率更高．
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