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Abstract

Lanthanide-doped upconversion nanomaterials (UCNMs) have been considered as a new generation of fluorescent materials for bioimaging due to their superior physicochemical features, such as large anti-Stokes shifts, low autofluorescence background, low toxicity and high penetration depth. However, tedious surface modifications have to be performed to stabilize UCNMs in hydrophilic environments, which is important for biomedical applications. The tutorial review offers a general overview of various strategies to transfer UCNMs from hydrophobic to hydrophilic for good bioapplications. More specifically, recent progress in designing UCNMs for multimodal bioimaging (such as upconversion luminescence (UCL) imaging, magnetic imaging (MRI), X-ray computed tomography (CT) and single-photon emission tomography (SPECT)) and multifunctional applications (drug release, photodynamic therapy and photothermal therapy) are presented in detail.

Keywords

Upconversion nanomaterials bioimaging modified multimodal

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The modified upconversion nanomaterials (UCNMs) for multimodal imaging and therapies

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