Design and engineering of magneto-responsive devices for cancer theranostics: Nano to macro perspective

•Magneto-responsive devices for cancer theranostics are reviewed.•Magnetic nanoparticles are used for cancer diagnostic through MRI.•Magnetic nanoparticles are clinically approved for magnetic hyperthermia application.•1D and 2D magnetic nanosystems have huge potential for cancer theranostics.•3D and 4D magnetic nanosystems still need further study and optimization. Design, research, and development of new and improved smart multifunctional devices is one of the main topics in the advanced functional materials agenda for the next decade. Smart materials that can be triggered by external stimuli are seen with high potential for innovative treatments and improved drug delivery systems by regulatory agencies like the FDA and EMA. The incorporation of magnetic nanostructures into complex systems produces multifunctional devices that can be spatiotemporally controlled by an external magnetic field. These magneto-responsive devices can be used for a multitude of biomedical applications, from diagnostic to the treatment of tumors, and are actively being developed and tested for cancer theranostics. Herein, we review the development of magneto-responsive devices for cancer theranostics, starting from the most straightforward architecture, single nanoparticles. We give some theoretical concepts about the design and production of such systems while providing a critical review of applications in clinical practice. Naturally, the review evolves to more complex architectures, from one-dimensional to three-dimensional magneto-responsive systems, demonstrating higher complexity and multifunctionality, and consequently, higher interest for clinical practice. The review ends with the main challenges in the design and engineering of magneto-responsive devices for cancer theranostics and future trends in this biomedical field.