The integration of diagnostic and therapeutic functionalities on a single theranostic nano‐system holds great promise to enhance the accuracy of diagnosis and improve the efficacy of therapy. Herein, a multifunctional polymeric nano‐micelle system that contains a photosensitizer chlorin e6 (Ce6) is successfully fabricated, at the same time serving as a chelating agent for Gd3+, together with a near‐infrared (NIR) dye, IR825. With a r1 relativity 7 times higher than that of the commercial agent Magnevist, strong fluorescence offered by Ce6, and high NIR absorbance attributed to IR825, these theranostic micelles can be utilized as a contrast agent for triple modal magnetic resonance (MR), fluorescence, and photoacoustic imaging of tumors in a mouse model. The combined photothermal and photodynamic therapy is then carried out, achieving a synergistic anti‐tumor effect both in vitro and in vivo. Different from single photo treatment modalities which only affect the superficial region of the tumor under mild doses, the combination therapy at the same dose using this agent is able to induce significant damage to both superficial and deep parts of the tumor. Therefore, this work presents a polymer based theranostic platform with great potential in multimodal imaging and combination therapy of cancer.

Red blood cells are attached to iron oxide nanoparticles pre-coated with chlorine e6, a photosensitizer, and then loaded with a chemotherapeutic drug, doxorubicin, to enable imaging-guided combined photodynamic and chemotherapy of cancer, achieving excellent synergistic therapeutic effects in an animal tumor model. This work highlights the great promise of integrating cell-based drug-delivery systems with nanotechnology as a biocompatible multifunctional platform for applications in cancer theranostics.

Recently, near‐infrared (NIR) absorbing conjugated polymeric nanoparticles have received significant attention in photothermal therapy of cancer. Herein, polypyrrole (PPy), a NIR‐absorbing conjugate polymer, is used to coat ultra‐small iron oxide nanoparticles (IONPs), obtaining multifunctional IONP@PPy nanocomposite which is further modified by the biocompatible polyethylene glycol (PEG) through a layer‐by‐layer method to acquire high stability in physiological solutions. Utilizing the optical and magnetic properties of the yielded IONP@PPy‐PEG nanoparticles, in vivo magnetic resonance (MR) and photoacoustic imaging of tumor‐bearing mice are conducted, revealing strong tumor uptake of those nanoparticles after intravenous injection. In vivo photothermal therapy is then designed and carried out, achieving excellent tumor ablation therapeutic effect in mice experiments. These results promise the use of multifunctional NIR‐absorbing organic‐inorganic hybrid nanomaterials, such as IONP@PPy‐PEG presented here, for potential applications in cancer theranostics.

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The booming development of nanomedicine offers great opportunities for cancer diagnostics and therapeutics. Herein, a magnetic targeting-enhanced cancer theranostic strategy using a multifunctional magnetic-plasmonic nanoagent is developed, and a highly effective in vivo tumor photothermal therapy, which is carefully planed based on magnetic resonance (MR)/photoacoustic (PA) multimodal imaging, is realized. By applying an external magnetic fi eld (MF) focused on the targeted tumor, a magnetic targeting mediated enhanced permeability and retention (MT-EPR) effect is observed. While MR scanning provides tumor localization and reveals time-dependent tumor homing of nanoparticles for therapeutic planning, photoacoustic imaging with higher spatial resolution allows noninvasive fi ne tumor margin delineation and vivid visualization of three dimensional distributions of theranostic nanoparticles inside the tumor. Utilizing the near-infrared (NIR) plasmonic absorbance of those nanoparticles, selective photothermal tumor ablation, whose effi cacy is predicted by real-time infrared thermal imaging intra-therapeutically, is carried out and then monitored by MR imaging for post-treatment prognosis. Overall, this study illustrates the concept of imaging-guided MF-targeted photothermal therapy based on a multifunctional nano-agent, aiming at optimizing therapeutic planning to achieve the most effi cient cancer therapy.