Preparation of porous aromatic framework/ionic liquid hybrid composite coated solid-phase microextraction fibers and their application in the determination of organochlorine pesticides combined with GC-ECD detection.

A novel hybrid material incorporating porous aromatic frameworks and an ionic liquid, 1-(triethoxy silyl)propyl-3-aminopropyl imidazole hexafluorophosphate, was prepared as solid-phase microextraction coating and employed for the extraction of organochlorine pesticides. Combining the advantages of porous aromatic frameworks and an ionic liquid, the fiber exhibited a high adsorption capacity for organochlorine pesticides. Under optimized experimental conditions, enhancement factors of 247-1696 were obtained with good linearity in the range of 1-500 mu g L-1. The detection limits and quantification limits were determined to be in the range of 0.11-0.29 mu g L-1 and 0.35-0.93 mu g L-1. The relative standard deviations for six replicates of organochlorine pesticides were in the range of 4.4%-7.2% and 5.7%-10.1% for one fiber and fiber-to-fiber, respectively. By coupling with a gas chromatography-electron capture detector, the novel fiber was successfully used for the determination of organochlorine pesticides in juice and milk samples with recoveries of 76.1%-121.3%.