Diagnosing or treating a human ear includes transporting a conjugated nanoparticle or a magnetically responsive nanoparticle into a human's middle or inner ear. Otologic nanophoresis includes electrically, magnetically or electromagnetically driving a nanoparticle through a membrane of the ear, including a tympanic membrane, a round window membrane, an oval window membrane, or a circulatory membrane. An otologic diagnostic device includes a nanoparticle conjugated with a material selected from the group consisting of lipids, proteins, growth factors, growth hormones, antioxidants, free radical scavengers, steroid preparations, and metabolically active substances; an otologic therapeutic device includes the same categories of substances and chemotherapeutic drugs. Another otologic composition includes a nanoparticle conjugated with a substance perceptible to magnetic resonance imaging.