Nano-iron oxide and precision magnetic diagnosis and treatment is a new medical technology to realize the early diagnosis and efficient treatment of diseases by using the magnetic and biocompatibility of nano-iron oxide particles. Nanosized iron oxide particles can be used as contrast agents for magnetic resonance imaging to enhance image contrast, and can also be used as the carrier of magnetic induction hyperthermia, drug delivery, cell regulation and other therapeutic means, to achieve precise positioning and controlled release through external magnetic field. Nanoiron oxide and precision magnetic diagnosis and treatment have the advantages of non-invasive, high efficiency, low toxicity and multi-function, which is a nanomedicine application with broad prospects.

As a contrast agent for magnetic resonance imaging, it can improve the image contrast between diseased tissues and normal tissues, and achieve high-resolution imaging of tumors, blood vessels, nerves, etc. For example, a "point-like" nuclear-shell structured nanoparticle, consisting of quasi-paramagnetic iron oxide and gadolinium oxide, can serve as an efficient T1 contrast agent to achieve targeted imaging of tumors.

In recent years, the synthesis technology, surface functionalization methods, and new discoveries and applications in the biomedical field, such as cell separation, biological detection, tumor therapy, etc.