Developing a Hetero-Trinuclear Erbium(III)–Copper(II) Complex Based on Apoferritin: Targeted Photoacoustic Imaging and Multimodality Therapy of Tumor

For the integration of targeted diagnosis
and treatment of tumor,
we innovatively designed and synthesized a single-molecule hetero-multinuclear
Er(III)–Cu(II) complex (ErCu2) and then constructed an ErCu2@apoferritin (AFt) nanoparticle (NP) delivery system. ErCu2 and ErCu2@AFt NPs not only provided an evident photoacoustic
imaging (PAI) signal of the tumor but also effectively inhibited tumor
growth by integrating photothermal therapy, chemotherapy, and immunotherapy. ErCu2@AFt NPs improved the targeting
ability and decreased the systemic toxicity of ErCu2 in vivo. Furthermore, we confirmed
that ErCu2 and ErCu2@AFt NPs inhibited tumor growth by inducing
apoptosis and autophagy of tumor cells and activating the immune system.
The study not only provides a novel strategy to develop therapeutic
metal agents but also reveals their potential for targeted accurate
diagnosis and multimodality therapy of cancer.