Functional tumor imaging based on inorganic nanomaterials

Inorganic nanomaterials have attracted substantial research interest due to their unique intrinsic physicochemical properties.We highlighted recent advances in the applications of inorganic nanoparticles regarding their imaging efficacy, focusing on tumor-imaging nanomaterials such as metal-based and carbon-based nanomaterials and quantum dots. Inorganic nanoparticles gain excellent in vivo tumor-imaging functions based on their specific characteristics of strong near-infrared optical absorption and/or X-ray attenuation capability. The specific response signals from these novel nanomaterials can be captured using a series of imaging techniques, i.e., optical coherence tomography(OCT), X-ray computed tomography(CT) imaging, two-photon luminescence(TPL), photoacoustic tomography(PAT), magnetic resonance imaging(MRI), surface-enhanced Raman scattering(SERS) and positron emission tomography(PET). In this review, we summarized the rapid development of inorganic nanomaterial applications using these analysis techniques and discussed the related safety issues of these materials.