A two-step ZnO nanoparticle-directed method has been implemented to prepare polymer monolith/zeolitic imidazolate framework (ZIF) solid-phase microextraction (SPME) fiber coatings with hierarchical micro-meso-macroporosity. The polymer/ZIF monolith was prepared on the surface of a stainless steel wire from a polymerization mixture containing dispersed ZnO nanoparticles. The embedded ZnO nanoparticles in the precursor polymer monolith coating were converted on-fiber to submicrometric porous crystals of the prototypical ZIF-8, based on the coordination of Zn(II) with 2-methylimidazole. The polymer/ZIF monolith coating was applied to the headspace SPME of benzene, toluene, ethylbenzene, and xylenes (BTEX) from water samples, followed by gas chromatography-flame ionization detection (GC-FID).

Hierarchically porous polymer/ZIF monolithic coatings showed a superior performance for BTEX extraction in comparison to coatings based on pure macroporous organic polymer monoliths, silicone glue/ZIF-8 coatings or commercial PDMS coatings. Experimental parameters such as desorption temperature, desorption time, salt concentration, temperature effect, equilibrium time and extraction time were investigated. Under the selected experimental conditions, limits of detection of 0.02–0.11 μg L⁻¹, linear ranges of 0.2–200 μg L⁻¹, relative standard deviations of 4.3–8.2%, and a fiber-to-fiber reproducibility of 8.9–9.8% (n = 3) were obtained. Recoveries higher than 88% were obtained for BTEX analysis in tap water, wastewater and landfill leachates.

已经实施了两步法进行ZnO纳米粒子定向的方法，以制备具有分级微介观巨相性的聚合物整料/沸石咪唑酸酯骨架（ZIF）固相微萃取（SPME）纤维涂层。由包含分散的ZnO纳米颗粒的聚合混合物在不锈钢丝的表面上制备聚合物/ ZIF整料。基于Zn（II）与2-甲基咪唑的配位作用，将前体聚合物整体涂层中嵌入的ZnO纳米粒子在纤维上转化为原型ZIF-8的亚微米级多孔晶体。将聚合物/ ZIF整体涂层应用于水样品中苯，甲苯，乙苯和二甲苯（BTEX）的顶空SPME，然后进行气相色谱-火焰电离检测（GC-FID）。

与基于纯大孔有机聚合物整体料的涂料，硅酮胶/ ZIF-8涂料或商用PDMS涂料相比，分层多孔聚合物/ ZIF整体涂料在BTEX萃取方面显示出优异的性能。研究了脱附温度，脱附时间，盐浓度，温度影响，平衡时间和提取时间等实验参数。在选定的实验条件下，检出限为0.02–0.11μgL ^-1，线性范围为0.2–200μgL ^-1，相对标准偏差为4.3–8.2％，并且纤维间的重现性为8.9–9.8获得％（n ＝ 3）。自来水，废水和垃圾渗滤液中的BTEX分析回收率高于88％。