Biodegradable polymer iron oxide nanocomposites: the future of biocompatible magnetism.

Abstract

Superparamagnetic iron oxide nanoparticles (SPIONs) have become increasingly popular for various biomedical applications. The superparamagnetic properties of these nanoparticles enable their magnetic manipulation of biological targets such as cells, proteins and nucleic acids. In addition, SPIONs allow for MRI contrast for cells and tissues. Although generally nontoxic, these particles on their own are not sufficiently biocompatible due to their inorganic nature. One strategy to circumvent this compatibility issue is to coat the SPIONs with a biocompatible polymer. Although polymer coating is effective at mitigating potential complications at the SPION/biological interface, this only scratches the surface of the functionality that can be enabled by polymer-SPION nanocomposites. For example, polymeric nanostructures can have multifunctional drug delivery abilities, including control of the delivery of biological payloads in both space and time. An emerging strategy is to combine the advantages of inorganic SPIONs with the drug delivery capabilities of biodegradable polymeric particles to create multifunctional theranostic polymer-SPION nanocomposites. By treating the SPIONs as a cargo to be loaded into larger biodegradable polymeric nanostructures, new nanocomposites can be created to unite the beneficial features of paramagnetism and controlled drug release into one single nanoparticle. Biodegradable polymer iron oxide nanoparticles are promising for applications to many areas of medicine.