Theoretical design and preparation of ionic liquid-based magnetic nanoparticles for the magnetic dispersive solid-phase extraction of benzimidazoles in human plasma

Conductor-like screening model for realistic solvents (COSMO-RS) theoretical chemical model is an effective tool for predicting the thermodynamic properties of solvents. In this study, 144 ionic liquids (ILs) were designed and screened by COSMO-RS with affinity interactions with benzimidazoles (BZDs) as the target. Ionic liquid-based magnetic nanoparticles (IL-MNPs, Fe 3 O 4 @SiO 2 @MAPs@PIL-POSS) were prepared by the selected diene ILs (1-allyl-3-vinylimidazolium chloride [Avim]Cl) and polyhedral oligomeric silsesquioxane (POSS) coating Fe 3 O 4 by free radical polymerization. As the adsorbent, the Fe 3 O 4 @SiO 2 @MAPs@PIL-POSS has great magnetic recovery ability and excellent specific adsorption ability for BZDs. The magnetic dispersive solid-phase extraction (MDSPE) of BZDs was established by optimizing the adsorption and desorption parameters. It is worth noting that the sample pretreatment only took 5 min. Combined with HPLC-MS/MS, a trace detection method for 7 trace BZDs in human plasma was established. In the method validation, the recoveries ranged from 79 % to 99 %, with relative standard deviations (RSDs) of 1.8 % to 8.8 %. The linear range were 1–1,000 μg/L. As a representative BZD, the adsorption kinetics and thermodynamic behavior of carbendazim on Fe 3 O 4 @SiO 2 @MAPs@PIL-POSS were analyzed to verify the adsorption mechanism, which is consistent with the results of IL screened by COSMO-RS. Therefore, it is feasible to theoretically screen IL and design IL-MNPs as specific adsorption materials. Furthermore, the theoretical design of MDSPE methods for target molecules has potential.