Full-spectrum responsive ZrO-based phototheranostic agent for NIR-II photoacoustic imaging-guided cancer phototherapy

• Published in: Biomaterials science 2020-11, Vol.8 (23), p.6515-6525
• Main Authors: Zhu, Chengyuan, Ding, Zhaoyang, Guo, Zhengxi, Guo, Xiaolu, Yang, Aijia, Li, Zhilang, Jiang, Bang-Ping, Shen, Xing-Can
• Format: Article
• ISSN: 2047-4830; 2047-4849
• DOI: 10.1039/d0bm01482f

Second near-infrared (NIR-II) window responsive phototheranostic agents have a precise spatiotemporal potential for the diagnosis and treatment of cancer. In this study, a full-spectrum responsive ZrO 2 -based phototheranostic agent was found to achieve NIR-II photoacoustic (PA) imaging-guided tumour-targeting phototherapy. Initially, the ZrO 2 -based phototheranostic agent was fabricated through NaBH 4 reduction to form boron-doped oxygen-deficient zirconia (ZrO 2− x -B), an amino-functionalised SiO 2 shell and a further covalent connection with hyaluronic acid (HA), namely, ZrO 2− x -B@SiO 2 -HA. In the ZrO 2− x -B@SiO 2 -HA system, the oxygen vacancy and boron doping resulted in full-spectrum absorption, enabling a high NIR-II photothermal conversion, high-resolution PA imaging ability and a remarkable production of reactive oxygen species (ROS). The surface modification of HA provided ZrO 2− x -B@SiO 2 -HA with water dispersibility and a targeting capability for CD44 overexpressed cancer cells. Furthermore, in vitro and in vivo experiments showed that NIR-II activated ZrO 2− x -B@SiO 2 -HA had a targeted photothermal/photodynamic effect for cancer elimination under the real-time guidance of NIR-II PAs. Hence, ZrO 2− x -B@SiO 2 -HA displays a precise NIR-II radiation-activated phototheranostic potential for PA imaging-guided cancer-targeting photothermal/photodynamic therapy. A second near-infrared window (NIR-II) responsive, cancer targeting ZrO 2 -based phototheranostic agent has been fabricated for imaging-guided precise synergetic phototherapy.