Two-Dimensional Graphene Augments Nanosonosensitized Sonocatalytic Tumor Eradication

Abstract

Ultrasound (US) can activate sonosensitizers for sonodynamic therapy (SDT), but the low activation efficiency and therapeutic outcome significantly hinder its further clinical translation. Inspired by the principles of semiconductor physics and photocatalysis chemistry, we herein report on augmenting the sonocatalytic efficiency of semiconductor TiO-based nanosonosensitizers for highly efficient SDT by the integration of two-dimensional (2D) ultrathin graphene with TiO nanosonosensitizers. The high electroconductivity of graphene facilitates the separation of the electron (e) and hole (h) pairs from the energy band of TiO and avoids their recombination upon external US irradiation; thus it significantly augments the therapeutic efficiency of TiO nanosonosensitizers for SDT against tumors. By further MnO functionalization, these 2D composite nanosonosensitizers achieved tumor microenvironment-sensitive (mild acidity) T-weighted magnetic resonance imaging of tumors for therapeutic guidance and monitoring. The high photothermal-conversion capability of graphene also synergistically enhanced the SDT efficiency, achieving the complete eradication of a tumor without reoccurrence. This work provides a paradigm for augmenting semiconductor TiO-based sonocatalytic therapeutic nanomedicine by learning the physiochemical principles from traditional photocatalysis, which also demonstrates a highly efficient noninvasive and safe therapeutic modality for tumor eradication by the nanosonosensitized sonocatalytic process.

Nanoparticle-assisted ultrasound: A special focus on sonodynamic therapy against cancer

“…6) [135]. More recently, Dai et al [136] developed a novel nanoconstruct (NC) functionalizing two-dimensional (2D) reduced graphene oxide (GR) with TiO 2 NPs (TiO 2 -GR NC). The high electroconductivity of graphene facilitated the separation of the sono-generated e − /h + pairs leading to higher ROS generation in-vitro.…”

2D Nanomaterials for Cancer Theranostic Applications

“…6) MnO x /TiO 2 –rGO nanocomposites for MR imaging‐guided synergistic SDT/PTT. Reproduced with permission . Copyright 2017, American Chemical Society.…”

“…As an ultrasound‐triggered therapy method, sonodynamic therapy (SDT) has attracted increasing attention because it overcomes crucial disadvantages, such as low penetration depth and high phototoxicity of PDT . In another study, Chen and co‐workers integrated rGO nanosheets with a titanium dioxide (TiO 2 ) sonosensitizer to improve the therapeutic outcome of SDT against cancer . The excellent electroconductivity of rGO nanosheets facilitates the separation of electron (e − )/hole (h + ) pairs from the energy band of TiO 2 and prevents their recombination under ultrasound waves, thus substantially enhancing the therapeutic efficiency of TiO 2 sonosensitizers for cancer killing during SDT.…”

Advanced Nanotechnology Leading the Way to Multimodal Imaging‐Guided Precision Surgical Therapy

“…SDT has the advantages in deeper tissue penetration and nonphototoxicity to NT compared with PDT, providing a promising cancer therapy paradigm and receiving an increasing amount of research attention. [347] MnO x /TiO 2 -GR-PVP provided tumor microenvironment-sensitive T 1 -weighted MRI for IGS. [347][348][349] They reported semiconductor TiO 2 -based nanosonosensitizers (named MnO x /TiO 2 -GR-PVP) with improved sonocatalytic efficiency by integrating ultrathin graphene that had high photothermal-conversion capability, thereby achieving SDT/PTT-based synergistic cancer therapy.…”

“…[343][344][345][346] Chen's team has been aggressively explored synergistic SDT for cancer therapeutics based on nanomedicine. [347][348][349] They reported semiconductor TiO 2 -based nanosonosensitizers (named MnO x /TiO 2 -GR-PVP) with improved sonocatalytic efficiency by integrating ultrathin graphene that had high photothermal-conversion capability, thereby achieving SDT/PTT-based synergistic cancer therapy. [347] MnO x /TiO 2 -GR-PVP provided tumor microenvironment-sensitive T 1 -weighted MRI for IGS.…”