Molecularly imprinted polymer based on ternary deep eutectic solvent and temperature-sensitive cellulose...

This study reports a thermoresponsive molecularly imprinted polymer (CMMs@MPS@MIP) for isofraxidin recognition, synthesized through integration of deep eutectic solvent (DES) as functional monomer, N-isopropylacrylamide (NIPAM) as thermosensitive unit, and cellulose microspheres as carrier matrix. Under optimized conditions, the MIP exhibited enhanced adsorption capacity (35.24 mg/g) compared to non-imprinted polymer (CMMs@MPS@NIP) adsorption capacity (11.24 mg/g). Temperature-regulated adsorption/desorption cycles were achieved through thermal switching between 303 K (adsorption) and 318 K (desorption). The material exhibited excellent reusability, retaining 92 % of its initial adsorption capacity (35.24 mg/g) after 5 adsorption-desorption cycles utilizing temperature switching. Adsorption kinetics demonstrated rapid equilibrium (120 min) and followed a pseudo-second-order model (R²= 0.9853), indicating chemisorption. Thermodynamic analysis confirmed spontaneous adsorption, fitting the Langmuir isotherm (R²= 0.990), consistent with monolayer adsorption. High selectivity was evidenced by an imprinting factor (IF) of 2.7 and significantly greater adsorption capacity for isofraxidin compared to structural analogs like esculetin and quercetin. Applied to Acanthopanax senticosus extract, CMMs@MPS@MIP achieved 95.06 % recovery of isofraxidin, enriching it from the crude extract. This work establishes a temperature-responsive imprinting strategy advancing natural product purification technologies.