A NIR-laser smart stimulus self-assembly nanosystem with acid-activatable for enhanced photothermal and chemotherapy against tumors

DOX (doxorubicin hydrochloride)@ZIF-8 (zeolitic imidazolate framework-8)/PVBP (polyvinyl pyrrolidone-black phosphorus) was developed, which achieves cooperative PTT (photothermal therapy) and pH-triggerable chemotherapy. The combination of chemotherapy and PTT has attracted tremendous attention due to its advantages such as high safety and effectiveness compared to traditional chemotherapy. However, DOX was utilized in conventional single-system chemotherapy accompanied by great limitations, such as strong side effects, drug resistance, and other shortcomings. Given that BP possesses the advantages of high efficiency of photothermal conversion and good photothermal stability, DOX was used as a responsive drug of NIR to prepare nanocomposites. In this study, the one-pot method was used to synthesize DOX@ZIF-8/PVBP, which possesses excellent light-to-heat conversion efficiency and therapeutic performance. The DOX@ZIF-8/PVBP is composed of DOX and multifunctional nano-carriers. The nano-carriers incorporate ZIF-8 and photothermal-capable black phosphorus nanosheets (BPNSs) which exhibited large drug loading and good photothermal properties. Under the near-infrared (NIR) radiation after endocytosis, the photothermal effect promoted drug release and internal escape. By combining diagnostic agents and therapeutic agents in a complete system at the same time, multifunctional nanocarriers show great potential in cancer medicine. Accordingly, the study shows that a composite nano-drug delivery system (DOX@ZIF-8/PVBP) can be used as an efficient synergistic system for chemotherapy and PTT to inhibit tumors, showing a good development prospect in chemical-photothermal combined treatment of cancer.