Multifunctional nanomaterials-enhanced synergistic sono-phototherapy: Breaking the limitation of monotherapy

As minimally or non-invasive therapeutic modalities for cancer treatment, phototherapy and sonotherapy have become a new trend for biomedicine because these treatments can only target the cancer cells while leaving the normal tissue undamaged and intact. However, single phototherapy or sonotherapy can obtain effective clinical effects only when the dose of nanomaterials responding to light and ultrasound is high enough. Therefore, it is significant to develop or explore new multifunctional nanomaterials that can simultaneously respond to ultrasound and light to enhance synergistic sono-phototherapy in the clinical cancer treatment. In this review, we summarize the recent developments of multifunctional nanomaterials responding to ultrasound and light, including organic nanomaterials modified by porphyrin and its derivatives, indocyanine green, etc., and inorganic nanomaterials such as titanium dioxide and inorganic piezoelectric nanomaterials. We further elaborate the latest research progress about these multifunctional nanomaterials in the cancer treatment. Particularly, the inorganic piezoelectric nanomaterials can generate a built-in electric field under ultrasound to adjust the separation of photogenerated carriers, which has potential applications to construct multifunctional nanomaterials and enhance tumor therapeutic effects.