Fabrication of Multifunctional Gd₂O₃/Au Hybrid Nanoprobe via a One-Step Approach for Near-Infrared Fluorescence and Magnetic Resonance Multimodal Imaging in Vivo

Facile fabrication of multimodal imaging probes is highly desired for bioimaging application due to their integrated advantages of several imaging modalities. Here, we report a simple and one-step mild strategy to fabricate a multifunctional Gd₂O₃/Au hybrid nanoprobe. Bovine serum albumin (BSA) was used as the template in the biomineralization synthesis. The fabricated BSA-Gd₂O₃/Au nanoprobe showed excellent chemical stability, intense near-infrared (NIR) fluorescence, and good magnetic resonance imaging (MRI) ability. The multimodal imaging potential of the prepared multifunctional nanoprobe was demonstrated by successful NIR fluorescent and magnetic resonance blood pool imaging. Further modification of BSA-Gd₂O₃/Au with arginine–glycine–aspartic acid peptide c­(RGDyK) (RGD) enabled the nanoprobe for targeted tumor imaging in vivo

Gadolinium Complexes Functionalized Persistent Luminescent Nanoparticles as a Multimodal Probe for Near-Infrared Luminescence and Magnetic Resonance Imaging <i>in Vivo</i>

The development of multimodal nanoprobes that combined properties of near-infrared (NIR) fluorescence and magnetic resonance imaging (MRI) within a single probe is very important for medical diagnosis. The NIR-emitting persistent luminescent nanoparticles (PLNPs) are ideal for optical imaging owing to no need for in situ excitation, the absence of background noise, and deep tissue penetration. However, no PLNP based multimodal nanoprobes have been reported so far. Here, we report a novel multimodal nanoprobe based on the gadolinium complexes functionalized PLNPs (Gd­(III)-PLNPs) for <i>in vivo</i> MRI and NIR luminescence imaging. The Gd­(III)-PLNPs not only exhibit a relatively higher longitudinal relaxivity over the commercial Gd­(III)-diethylenetriamine pentaacetic acid complexes but also keep the superlong persistent luminescence. The prepared Gd­(III)-PLNPs multimodal nanoprobe offers great potential for MRI/optical imaging <i>in vivo</i>

Incorporation of Computed Tomography and Magnetic Resonance Imaging Function into NaYF₄:Yb/Tm Upconversion Nanoparticles for in Vivo Trimodal Bioimaging

Rational design and fabrication of multimodal imaging nanoprobes are of great significance for in vivo imaging. Here we report the fabrication of a multishell structured NaYF₄:Yb/Tm@NaLuF₄@NaYF₄@NaGdF₄ nanoprobe via a seed-mediated epitaxial growth strategy for upconversion luminescence (UCL), X-ray computed tomography (CT), and magnetic resonance (MR) trimodal imaging. Hexagonal phase NaYF₄:Yb/Tm is used as the core to provide UCL, while the shell of NaLuF₄ is epitaxially grown on the core not only to provide an optically inert layer for enhancing the UCL but also to serve as a contrast agent for CT. The outermost NaGdF₄ shell is fabricated as a thin layer to give the high longitudinal relaxivity (<i>r</i>₁) desired for MR imaging. The transition shell layer of NaYF₄ not only provides an interface to facilitate the formation of NaGdF₄ shell but also inhibits the energy transfer from inner upconversion activator to surface paramagnetic Gd³⁺ ions. The fabricated multishell structured nanoprobe shows intense near-infrared UCL, high <i>r</i>₁ value of 3.76 mM^–1 s^–1, and in vitro CT contrast effect. The multishell structured nanoprobe offers great potential for in vivo UCL/CT/MR trimodal imaging. Further covalent bonding of folic acid makes the multishell structured nanoprobe promising for in vivo targeted UCL imaging of tumor-bearing mice