Hollow periodic mesoporous organosilicas for highly efficient HIFU-based synergistic therapy

Nano-biotechnology provides a promising therapeutic strategy for the development of novel cancer therapeutic modalities. In this work, molecularly organic-inorganic hybrid hollow periodic mesoporous organosilicas (HPMOs) were elaborately designed and fabricated by a silica-etching strategy for concurrent high intensity focused ultrasound (HIFU)-based synergistic therapy and combined HIFU-triggered chemotherapy. Due to the unique hollow nanostructures and well-defined spherical morphology, HPMOs themselves have been demonstrated as an efficient synergistic agent to enhance the HIFU ablation efficiency. The well-defined mesoporous shell and large hollow interior can function as the reservoirs for anticancer agents, and the drug (doxorubicin)-releasing exhibits the intelligent on demand profiles under HIFU irradiation due to the specific framework-induced pi-pi supramolecular stacking between benzene group-bridged framework and doxorubicin molecules. Combined with HIFU ablation and chemotherapy, HPMOs-based intelligent drug delivery nanosystems have demonstrated in vivo that anticancer drug-loaded HPMOs can significantly enhance the HIFU therapeutic outcomes due to the combined effects of concurrent enhancement of HIFU ablation and HIFU-triggered chemotherapy. This report gives the first evidence that mesoporous material-based drug delivery nanosystems (e. g., HPMOs) can improve the efficiency of focused ultrasound for cancer surgery, which can be further extended for the development of novel HIFU-based therapeutic modalities for more efficient cancer therapy with mitigated side-effects.