Unraveling the synergistic adsorption mechanism via DFT: SUPRADES-functionalized CMPs for highly sensitive detection...

A novel synergistic adsorbent was developed by integrating supramolecular deep eutectic solvents (SUPRADES) with dynamic recognition properties into conjugated microporous polymers (CMPs) via a supramolecular functionalization strategy, which was successfully employed for the quantification of trace thidiazuron (TDZ) in Ophiopogon japonicus. Coupled with high-performance liquid chromatography-ultraviolet detection (HPLC-UV) analysis, DES2-CMP-NH₂ emerged as the optimal material, showcasing an exceptional TDZ adsorption capacity of 22.03 mg·g^-1 and high potential for advanced sample pretreatment. Comprehensive density functional theory (DFT) calculations were employed to provide molecular-level insights into the adsorption mechanism, revealing synergistic effects involving π-π interactions, hydrogen bonding, and host-guest complexation that account for the superior performance. Building upon this fundamental understanding, a pipette-tip solid-phase extraction (PT-SPE) methodology was established, which demonstrated outstanding analytical performance: detection limit of 0.0075 μg mL^-1, quantification limit of 0.0250 μg mL^-1, and recovery rates of 87.85-98.86% with RSDs below 3.63%. The adsorbent exhibited superior adsorption efficiency compared to commercial adsorbents and maintained well-preserved performance over multiple cycles, demonstrating exceptional stability and reusability.