Magnetic Fe3O4@ZIF-8 nanoparticles as a drug release vehicle: pH-sensitive release of norfloxacin and its antibacterial activity

Metal-organic frameworks (MOFs) have a high specific surface area and inherent biodegradability due to their unique structure and composition . As well, owing to the properties of nanomaterials and especially their magnetic features, Fe 3 O 4 nanoparticles and MOFs composite materials have great potential in the design and application of drug release. The present work: firstly, investigated norfloxacin loading in magnetic metal organic framework (Fe 3 O 4 @ZIF-8); and secondly, studied the release of norfloxacin and its antibacterial activity . Results showed the release efficiencies reached 97 % at 310 K after 84 h (pH 7.4). Drug release behavior was tested at various pH levels and it was found that Fe 3 O 4 @ZIF-8 has pH-sensitive properties. Furthermore, the release model calculation illustrated that the release process fitted well to the Bhaskar model. The magnetic properties of Fe 3 O 4 @ZIF-8 confirmed that the composite has potential application for a targeted drug delivery system. The mechanism of pH-responsive norfloxacin release was combined with diffusion , ion exchange and electrostatic repulsion. Furthermore, the antibacterial activities of Fe 3 O 4 @ZIF-8 and NOR-Fe 3 O 4 @ZIF-8 were tested against Escherichia coli . Results showed that Fe 3 O 4 @ZIF-8 had good biocompatibility while NOR-Fe 3 O 4 @ZIF-8 can deter or inhibit the actions of microorganisms .