Multifunctional nanoplatform based on tetragonal BaTiO3-Au@polydopamine for computed tomography imaging-guided photothermal synergistic and enhanced piezocatalytic cancer therapy

Non-centrosymmetric tetragonal barium titanate nanocrystals have the potential to serve as piezoelectric catalysts in cancer therapy. When exposed to ultrasound irradiation, BaTiO 3 can generate reactive oxygen species with a noninvasive and deep tissue-penetrating approach. However, the application of BaTiO 3 in cancer nanomedicine is limited by their biosafety, biocompatibility, and dosage efficiency. To explore the potential application of BaTiO 3 in nanomedical cancer treatment, we introduced ultra-small Au nanoparticles onto the surface of BaTiO 3 to enhance the piezoelectric catalytic performance. Additionally, we also coated the BaTiO 3 with polydopamine to improve their biosafety and biocompatibility. This led to the preparation of a novel multifunctional BaTiO 3 -based nanoplatform called BTAPs. In vitro and in vivo experiments demonstrated that the incorporation of Au dopants and polydopamine coating successfully improved the piezoelectric catalysis properties and biocompatibility of BaTiO 3 . Compared with unmodified BaTiO 3 , BTAPs achieved a similar piezoelectric catalytic effect at a low dose (0.3 mg ml −1 in vitro and 10 mg kg −1 in vivo ). Moreover, BTAPs also exhibited enhanced properties in computed tomography imaging and photothermal effects in vivo . Therefore, BTAPs offer valuable insights into the advantages and limitations of piezoelectric catalytic nanomedicine in cancer treatment.