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Mn₃[Co(CN)₆]₂@SiO₂ core-shell nanocubes: novel bimodal contrast agents for MRI and optical imaging.

ABSTRACT: Nanoprobes with dual modal imaging of magnetic resonance imaging (MRI) and two-photon fluorescence (TPF) can serve as promising platforms for clinical diagnosis. A wide range of molecules and nanoparticles have been investigated as agents for contrast enhanced MRI and fluorescence imaging in cancer diagnosis. However, a single material with dual modal imaging of MRI and TPF is rarely reported. We found that Mn₃[Co(CN)₆]₂@SiO₂ nanocubes can serve as agents for both T₁- and T₂-weighted MRI, and TPF imaging. The nanocubes coated with silica to form Mn₃[Co(CN)₆]₂@SiO₂ core-shell nanocubes were readily internalized by cells without showing cytotoxicity. In vitro tests, the core-shell nanocubes display relatively high longitudinal (r₁) and transverse (r₂) relaxivities, they also manifest a remarkable T₁ and T₂ contrast effects at in-vivo imaging of internal organs in Mice. Moreover, the core-shell nanocubes could offer high-resolution cell fluorescence imaging by two-photon excitation (720 nm) or by conventional fluorescence with 403- or 488-nm excitation.

SUBMITTER: Huang Y

PROVIDER: S-EPMC3770959 | biostudies-literature |

REPOSITORIES: biostudies-literature

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