Chitosan-coated iron oxide nanoparticles for molecular imaging and drug delivery

Iron oxide nanoparticles (IONPs) are a new class of nanomaterials which have attracted extensive interest for application in in vivo magnetic resonance imaging (MRI) due to their intrinsic superparamagnetic and biodegradable properties. Performance of the IONPs is largely dependent upon the properties of their surface coatings, which serve to prevent nanoparticle agglomeration, reduce the risk of immunogenicity, and limit nonspecific cellular uptake. Among the coating materials studied to date, chitosan has drawn considerable attention. Commonly derived from crustacean shells, chitosan is a natural linear polysaccharide and has ample reactive functional groups that can serve as anchors for conjugation of therapeutics, targeting ligands, and imaging agents. Because of these unique attributes, chitosan-coated IONPs are becoming more desirable for cancer imaging and therapy applications. This chapter discusses the current advances and challenges in synthesis of chitosan-coated IONPs, and their subsequent surface modifications for applications in cancer diagnosis and therapy.