Urushiol-dextran SPIONs magnetic recyclable nanoparticles immobilizing vancomycin (V@DU@Fe) for antibacterial application.

In this study, magnetic nanocarriers (DU@Fe, D = 281.6 nm, zeta potential -28.0 mV) were fabricated using dextran, urushiol as the shell and superparamagnetic iron oxide nanoparticles (SPIONs) as the core. Subsequently, the specific ligand Lys-D-Ala-D-Ala of vancomycin (Van) was grafted onto the surface of DU@Fe, which generated nanoparticles (Lys-D-Ala-D-Ala@DU@Fe) with an average particle size of 385.5 nm and a zeta potential of -16.8 mV via specific and robust interaction. Ultimately, the immobilization capacity of Van reached up to 294.1 mg·g for efficient antibacterial properties. Moreover, the assembly process adhered to the pseudo-second-order kinetics model (R = 0.998-0.999) and the Langmuir adsorption isotherm model (R = 0.999, 30 °C). Notably, V@DU@Fe effectively adhered to the cell envelopes of both Gram-negative and Gram-positive bacteria, achieving rapid bactericidal effects within 1 h. Furthermore, it maintained over 85.0 % of its initial antibacterial efficiency against S. aureus and S. epidermidis even after six recycles. Therefore, this study provides strategies and methods for the development of urushiol-dextran intelligent SPIONs nanomedicines.