Organic–inorganic hybrid photothermal nanomaterials for combined photothermal and chemotherapy therapy of tumors under the dual biological window

In view of the advantages of non-invasive photothermal therapy (PTT) in the clinical treatment of tumors, such as high efficiency of tumor ablation and less side effects, combination therapy based on PTT has attracted widespread attention. In this study, organic–inorganic hybrid nanoparticles (NPs) of PANI@W 18 O 49 with uniform morphology and PANI@W 18 O 49 @Fe 3 O 4 with magnetic targeting were synthesized by hydrothermal method. It was found that the hybrid NPs not only did not affect the photothermal properties of W 18 O 49 , but also improve its antioxidant properties, which made the synthesized NPs more suitable for PTT as a photothermal agent than W 18 O 49 itself. The results of absorbance and photothermal measurement of NPs under different wavelengths (808 and 1064 nm) show that the photothermal performance of hybrid NPs is stable. The photothermal conversion efficiency of PANI@W 18 O 49 under 808 and 1064 nm laser irradiation can reach to 50.43 and 30.69%, respectively, and that of PANI@W 18 O 49 @Fe 3 O 4 can also reach to 63.9 and 32.55%; the photothermal temperature can induce apoptosis of cancer cells. In drug release experiments, it was demonstrated that the hybrid NPs could control the release of DOX under the dual stimulus response (pH and temperature) to reduce the side effects caused by the uncontrolled release of drug under physiological conditions. In addition, the survival rate of cancer cells decreased to 20.05 and 22.33% by NIR irradiation after co-incubation of drug-loaded NPs, indicating that the prepared hybrid NPs have the potential to be applied in the combined treatment of photothermal and chemotherapy for cancer. Graphical Abstract Preparation methods of PW and PWF NPs and schematic diagram of their application in chemotherapy/photothermal combined therapy for tumors.