Heterogeneous Structure‐Based AuNBs@TiO₂ Nano‐Photosensitizers for Computed Tomography Imaging Guided NIR‐II Photodynamic Therapy and Cancer Metastatic Prevention

AbstractPhotodynamic therapy (PDT) is a minimally invasive cancer treatment that, despite its significant attention, faces limitations in penetration depth that restrict its effectiveness. Herein, we found that gold nanobipyramid (AuNBs) coated with TiO2 can form a core‐shell heterogeneous structure (AuNBs@TiO2) with strong absorption at second near infrared (NIR‐II) region. A substantial quantity of reactive oxygen species (ROS), including singlet oxygen (1O2), superoxide anion radicals, and hydroxyl radicals, can be rapidly generated when subjecting the AuNBs@TiO2 aqueous suspension to 1064 nm laser irradiation. The quantum yield for sensitization of 1O2 by AuNBs@TiO2 is 0.36 at 1064 nm light excitation. In addition, the Au element as high‐Z atoms in the nanosytem can improve the ability of computed tomographic (CT) imaging. As compared to commercial iohexol, the AuNBs@TiO2 nanoparticle exhibits significantly better CT imaging effect, which can be used to guide PDT. In addition, the nano‐photosensitizer shows a remarkable therapeutic effect against established solid tumors and prevents tumor metastasis and potentiates immune checkpoint blockade therapy. More importantly, this work highlights the great potentials of AuNBs@TiO2 as a theranostic platform for CT guided cancer photodynamic immunotherapy.This article is protected by copyright. All rights reserved