Dual-core@shell-structured Fe3O4–NaYF4@TiO2 nanocomposites as a magnetic targeting drug carrier for bioimaging and combined chemo-sonodynamic therapy

Multifunctional dual-core@shell (Fe3O4–NaYF4@TiO2) nanocomposite (DCSNC) loaded with doxorubicin (DOX) have been developed for synergetic sonodynamic cancer chemotherapy, where titanium dioxide (TiO2) is employed as a sonosensitizer for sonodynamic therapy (SDT) of the tumor in deep tissues, and NaYF4 is used for upconversion luminescence (UCL) imaging. After being coated with hyaluronic acid (HA), the nanocomposites exhibit a time dependent cellular uptake and an excellent nucleus targeting effect in KB and MCF-7 cells. The ultrasound of HA–DCSNCs obviously enhances the apoptosis rate of MCF-7 cells. A greater tumor inhibition rate is observed when the tumor-bearing mice are treated with combined therapy (88.36%) compared with chemotherapy (28.36%) or sonodynamic therapy (38.91%) alone, indicating the potential of sonodynamic chemotherapy for cancer treatment.