BiVO4/Fe3O4@polydopamine superparticles for tumor multimodal imaging and synergistic therapy

Abstract Background Despite tremendous progress has been achieved in tumor theranostic over the past decade, accurate identification and complete eradication of tumor cells remain a great challenge owing to the limitation of single imaging modality and therapeutic strategy. Results Herein, we successfully design and construct BiVO 4 /Fe 3 O 4 @polydopamine (PDA) superparticles (SPs) for computed tomography (CT)/photoacoustic (PA)/magnetic resonance (MR) multimodal imaging and radiotherapy (RT)/photothermal therapy (PTT) synergistic therapy toward oral epithelial carcinoma. On the one hand, BiVO 4 NPs endow BiVO 4 /Fe 3 O 4 @PDA SPs with impressive X-ray absorption capability due to the high X-ray attenuation coefficient of Bi, which is beneficial for their utilization as radiosensitizers for CT imaging and RT. On the other hand, Fe 3 O 4 NPs impart BiVO 4 /Fe 3 O 4 @PDA SPs with the superparamagnetic property as a T 2 -weighted contrast agent for MR imaging. Importantly, the aggregation of Fe 3 O 4 NPs in SPs and the presence of PDA shell greatly improve the photothermal conversion capability of SPs, making BiVO 4 /Fe 3 O 4 @PDA SPs as an ideal photothermal transducer for PA imaging and PTT. By integrating advantages of various imaging modalities (CT/PA/MR) and therapeutic strategies (RT/PTT), our BiVO 4 /Fe 3 O 4 @PDA SPs exhibit the sensitive multimodal imaging feature and superior synergistic therapeutic efficacy on tumors. Conclusions Since there are many kinds of building blocks with unique properties appropriating for self-assembly, our work may largely enrich the library of nanomateirals for tumor diagnosis and treatment.