Liposome encapsulated hemoglobin modified Au@TiO2 for sonodynamic therapy

Abstract Sonodynamic therapy (SDT) has attracted considerable attention owing to its large penetration depth. However, the low efficiency of traditional sonosensitizers and the hypoxia environment of deep tumors hinder their therapeutic effect in practical application. Herein, the Au@TiO2-hemoglobin loaded liposome (Au@TiO2-Hb-Lip) complex has been constructed to improve the efficiency of SDT against hypoxic tumors. The results indicate that the generated carriers upon ultrasound activation of TiO2 nanoparticles (NPs) can be effectively trapped by Au NPs, and the production of reactive oxygen species (ROS) is increased by two times compared to that of bare TiO2 NPs. Particularly, the introduction of liposomes as a carrier and hemoglobin as an oxygen supplier not only prevents the aggregation of Au@TiO2 NPs in the blood environment but also improves the adaptability of Au@TiO2-Hb-Lip to hypoxic tumors. These synergic actions of different moieties in Au@TiO2-Hb-Lip sonosensitizer significantly enhance the SDT efficiency.