Magnetic graphene consists of reduced graphene oxide loaded with magnetic Fe3O4 nanoparticles, which has magnetic responsiveness, catalytic properties, and conductive/thermal conductivity of graphene.  Therefore, it can be used for magnetic separation of biomolecules, biocatalysis as a simulated enzyme, environmental pollution treatment, construction of composite materials doped with polymers, construction of nanomedicine carriers, development of biosensing and detection methods, etc.