Drug Release Behavior of Enrofloxacin Molecularly Imprinted Polymer Synthesized via Electron Beam Irradiation

Traditional thermal polymerization for imprinted polymers suffers from long reaction time and initiator residues. This study proposes an initiator-free and fast reaction electron beam irradiation technique to synthesize enrofloxacin (ENRO) molecularly imprinted polymers (MIPs) for sustained drug release. ENRO-based MIPs were prepared using methacrylic acid (MAA) as a functional monomer and ethylene glycol dimethacrylate (EGDMA) as a crosslinker under electron beam irradiation within 2 h. The structure was characterized by SEM, FTIR, DSC, and TG. Drug loading capacity was determined via solvent elution, and drug release behavior was evaluated in simulated physiological environments. The MIP exhibited a high drug loading ratio of 13.27% and porous morphology (SEM). FTIR confirmed complete template removal, while thermal analysis indicated uniform drug dispersion and enhanced stability. Cumulative release was pH-dependent: 72.12% at pH 7.4 (physiological) and 41.67% at pH 1.2 (gastric). Drug release kinetics followed the Korsmeyer-Peppas model (R² > 0.88), dominated by Fickian diffusion. Electron beam irradiation enables initiator-free synthesis of ENRO-based MIP with high loading capacity and pH-responsive sustained release, offering significant potential for targeted antibiotic delivery.