Theranostic Applications of Stimulus-Responsive Systems based on Fe₂O₃

According to the interaction of nanoparticles with biological systems, enthusiasm for nanotechnology in biomedical applications has been developed in the past decades. Fe₂O₃ nanoparticles, as the most stable iron oxide, have special merits that make them useful widely for detecting diseases, therapy, drug delivery, and monitoring the therapeutic process. This review presents the fabrication methods of Fe₂O₃-based materials and their photocatalytic and magnetic properties. Then, we highlight the application of Fe₂O₃-based nanoparticles in diagnosis and imaging, different therapy methods, and finally, stimulus-responsive systems, such as pH-responsive, magneticresponsive, redox-responsive, and enzyme-responsive, with an emphasis on cancer treatment. In addition, the potential of Fe₂O₃ to combine diagnosis and therapy within a single particle called theranostic agent will be discussed.