A boronate-affinity thermoresponsive molecularly imprinted resin as a green solid-phase extraction filler for highly selective adsorption of psoralen

Traditional solid-phase extraction techniques frequently suffer from insufficient molecular recognition capability, especially when discriminating structurally analogous compounds. To overcome this challenge, we developed a novel thermoresponsive molecularly imprinted resin (TMIR-PDA@X-5) via a multi-dimensional functionalization strategy, enabling highly selective adsorption of psoralen (PSO). The X-5 macroporous resin provided an ideal scaffold with its three-dimensional porous structure and high surface area. A polydopamine (PDA) interlayer was formed via in situ self-assembly, enabling stable functional group grafting. The material combined N-isopropylacrylamide (NIPAM) and 4-vinylphenylboronic acid (4-VPBA) to achieve intelligent molecular recognition: 4-VPBA selectively bound PSO through hydrogen bonding and π-π interactions, while NIPAM’s thermoresponsive properties created a temperature-regulated “molecular gate”. The contraction of polymer chains above the lower critical solution temperature (LCST) exposed the imprinted cavities, resulting in a PSO adsorption capacity of 56.32 mg·g −1 . Meanwhile, reversible temperature regulation below the LCST achieved a desorption efficiency of 91.95 %. The reusability of TMIR-PDA@X-5 was evaluated through ten adsorption–desorption cycles, demonstrating excellent performance with 81.72 % retention of its initial adsorption capacity. Moreover, the material maintained a high desorption rate of 87.29 %, underscoring its potential for sustainable applications. The application of TMIR-PDA@X-5 for the adsorption of the Ficus carica L. leaf extract achieved a high PSO adsorption efficiency of 85.83 %. This work presents a green solid-phase extraction filler, offering a novel strategy for the selective separation of natural products using molecularly imprinted material.