Triazine-based porous organic framework as adsorbent for solid-phase microextraction of some organochlorine pesticides.

Triazine-based porous organic frameworks (POFs) were constructed through a Friedel-Crafts reaction of cyanuric chloride (CC) with triphenylamine (TPA) monomers. The obtained POFs (CC-TPAs) were explored as the solid-phase microextraction (SPME) fiber coatings for the extraction of the organochlorine pesticides (OCPs). It was found that the mesoporous volume of the CC-TPAs was the main factor for their SPME adsorption performance. The CC-TPA-based fiber was successfully used for the SPME of the OCPs from fruit samples (apple, peach and pear). With the help of gas chromatography-micro-electron capture detection, the CC-TPA-based SPME method showed high enrichment factors (146-456), low limits of detection (0.032-0.090 ng g-1), good linearity (0.11-20 ng g-1, r2 > 0.991) and satisfactory repeatability (relative standard deviations <10.5%) for the OCPs. The method recoveries for spiked OCPs at the concentrations of 0.5, 2.0 and 10.0 ng g-1 in fruit samples were in the range of 86.0-114.0%, 83.5-116.5% and 81.1-118.6%, respectively. The CC-TPA coated fiber was stable enough for 100 extraction cycles without significant loss of the extraction efficiency.