Tailoring porous polymer for online highly efficient in-capillary solid phase microextraction of nonsteroidal anti-inflammatory drugs reinforced by magnetic field.

Efficient microextraction is essential in the sensitive and accurate monitoring of non-steroidal anti-inflammatory drugs (NSAIDs) residuals in complex samples. In the present study, a new porous monolith doped with magnetic nanoparticles (PDMP) was in-situ tailored in capillary using diallylamine and 1-allyl-3-methylimidazolium chloride as dual functional monomers. The obtained PDMP was employed as microextraction media of in-capillary solid phase microextraction reinforced by magnetic field (MR-IC-SPME) for the highly efficient microextraction of NSAIDs. Results evidenced that the magnetic field applied during extraction process was a pivotal factor to enhance the extraction efficiencies which were improved from 31.0% to 61.4% (absence of magnetic field) to 61.2-93.6%. The adsorption capacities of PDMP towards the studied NSAIDs were 9.3-14.3 mg/g. Practicality of the introduced PDMP@MR-IC-SPME was demonstrated by online hyphenation with HPLC to sensitively and reliably monitor NSAIDs residuals in environmental water and human urine samples under the optimal microextraction parameters. The detection limits and fortifying recoveries were in the ranges of 0.0018-0.0056 μg/L and 80.1-119%, respectively, and the RSDs for intra-day and inter-day precision varied from 1.1% to 9.8%. Moreover, the adsorption behaviors and mechanism were investigated in detail. Accuracy and greenness of the developed online approach were inspected by confirmatory experiments and various metric tools, respectively, confirming the method's reliability and greenness as a useful alternative for monitoring NSAIDs residuals in complex samples.