Mature magnetosomes have a species-specific shape with crystal sizes from 30 nm to 100 nm. The presence of a lipoprotein membrane extends the range of their possible applications through modification of membrane proteins. Magnetosomes usually form chains inside the bacteria and create a powerful magnetic dipole, facilitating the movement along the lines of the Earth's magnetic field. Magnetosomes have unique properties and advantages in comparison with magnetic nanoparticles obtained by chemical methods. It has been demonstrated that magnetosomes can be used for magnetic separation of cells and proteins, as well as DNA and RNA extraction directly from biological fluids.

New approaches currently being developed in medicine are based on synthetic magnetic particles, which are used for the targeted delivery of chemotherapeutic agents to the affected organ, either as contrast agents in magnetic resonance imaging or for treatment of malignant tumours (see magnetic nanoparticles for therapeutic use).