Abstract
Clearly delineating the tumor foci based on multimodal imaging techniques and precisely guiding the minimally invasive therapy are pivotal to completely remove tumors, especially for early micro-tumor lesions. Nevertheless, single-mode imaging techniques are difficult to accurately visualize the tumor region, and the mono-therapeutic strategy is hardly a complete removal of the tumor. In this study, we prepare a biodegradable amphiphilic polymer containing poly(aspartic acid). It is further self-assembled with Bi(3+) and ultrasmall Fe(3)O(4) to form a multifunctional nanocomplex (Bi/Fe(3)O(4)@P3), which served as a CT/MRI dual-imaging contrast agent and enhanced the photothermal/chemodynamic synergistic therapy. In addition, to enhance the photothermal efficiency, the thermal stress also elevated the level of intracellular H(2)O(2), which would facilitate the Fenton reaction between Bi(3+)/Fe(2+) and H(2)O(2) and improve the chemodynamic therapy (CDT) efficacy. Particularly, Bi/Fe(3)O(4)@P3 would concurrently deplete the abundant intracellular GSH through the coordination of Bi(3+) with GSH to further potentiate the PTT/CDT synergistic tumoricidal efficacy. Therefore, our study was expected to provide a promising theranostic nano-agent and potential comprehensive therapeutic strategy for microtumors.