In vitro thermo-triggered drug release from magnetic polyurethane-urea nanocomposite

Abstract To achieve efficient therapeutic effect and limit side effects, an in vitro thermo-triggered drug release was designed. Superparamagnetic iron oxide nanoparticles (SPIO NPs) was synthesized, loaded by Norfloxacin (NOR) as a model drug and coated with polyurethane urea (PUU). PUU was prepared using isophorondiisocyanate, polyethylene glycol with different molecular weights and water as a chain extender. A hierarchical morphology and thermal behavior of the resulting nanocomposites (NOR@SPIO-PUU) were examined by XRD, SEM, TEM, TGA and zeta potential analyzer. The effects of different amounts of SPIO NPs and concentration of drug on loading capacity were investigated. The release behavior of the drug is influenced by the composition of the carriers, loading capacity of the drug, pH, ionic strength and temperature. At 25 °C, none of drug is released from NOR@SPIO(3)-PUU(400) while at slightly elevated temperature 37 °C, a controlled release of the drug was observed however, at 45 °C a burst release was detected. The mechanism of drug release, antimicrobial efficacy and cytotoxic effect of nanocomposite loaded drug were investigated. The release of the drug from NOR@SPIO(3)-PUU(400) at 37 °C follows Fickian diffusion mechanism however, at 45 °C follows first order mechanism. The nanocomposite loaded drug (NOR@SPIO(3)-PUU(400)) demonstrated 2- fold increase in antibacterial efficacy against E-Coli, compared with free drug. A significant cytotoxicity of NOR@SPIO(3)-PUU(400) against MCF-7 cell lines cell lines was noticed with moderate effect on Human lung fibroblast cell line (WI38).