Metal-organic aerogel as a coating for solid-phase microextraction.

An iron-based metal-organic aerogel was synthesized using metal-organic framework nanoparticles and applied as a fiber coating for solid-phase microextraction (SPME). Chemical, thermal and morphological characteristics of the material were investigated. Headspace SPME followed by gas chromatography-electron capture detection was used for the determination of chlorobenzenes in the environmental samples. The key experimental factors affecting the extraction efficiency of the analytes, such as ionic strength, extraction and desorption temperature, and extraction time were investigated and optimized. The applicability of the coating for the extraction of chlorobenzenes from the environmental samples including river and tap water, sludge, and coastal soil was evaluated. The detection limits were in the range of 0.1-60 ng L-1. The relative standard deviations were between 2.0 and 5.0%. The extraction recovery of the analytes was in the range of 88-100%. Compared to the commercial PDMS fiber, the present fiber showed better extraction efficiency.