... :8nm40-60nm100nm300nm500nm1000nm2800nm2. Purity: 99.8% 3. MagneticNano Fe Oxide Powder Fe3O4 application range:1. Chemical industry, plastic, textile, painting, rubber, pigment ... absorbing material.5. Biological medical, magnetic drug carrier, sparse cell isolation, magnetic heat therapy materials, etc.6. Magnetic care materials.7. Magnetic recording material.