Vacancy defect-promoted nanomaterials for efficient phototherapy and phototherapy-based multimodal Synergistic Therapy.

Phototherapy and multimodal synergistic phototherapy (including synergistic photothermal and photodynamic therapy as well as combined phototherapy and other therapies) are promising to achieve accurate diagnosis and efficient treatment for tumor, providing a novel opportunity to overcome cancer. Notably, various nanomaterials have made significant contributions to phototherapy through both improving therapeutic efficiency and reducing side effects. The most key factor affecting the performance of phototherapeutic nanomaterials is their microstructure which in principle determines their physicochemical properties and the resulting phototherapeutic efficiency. Vacancy defects ubiquitously existing in phototherapeutic nanomaterials have a great influence on their microstructure, and constructing and regulating vacancy defect in phototherapeutic nanomaterials is an essential and effective strategy for modulating their microstructure and improving their phototherapeutic efficacy. Thus, this inspires growing research interest in vacancy engineering strategies and vacancy-engineered nanomaterials for phototherapy. In this review, we summarize the understanding, construction, and application of vacancy defects in phototherapeutic nanomaterials. Starting from the perspective of defect chemistry and engineering, we also review the types, structural features, and properties of vacancy defects in phototherapeutic nanomaterials. Finally, we focus on the representative vacancy defective nanomaterials recently developed through vacancy engineering for phototherapy, and discuss the significant influence and role of vacancy defects on phototherapy and multimodal synergistic phototherapy. Therefore, we sincerely hope that this review can provide a profound understanding and inspiration for the design of advanced phototherapeutic nanomaterials, and significantly promote the development of the efficient therapies against tumor.

Boron Dipyrromethene Nano-Photosensitizers for Anticancer Phototherapies.

As traditional phototherapy agents, boron dipyrromethene (BODIPY) photosensitizers have attracted increasing attention due to their high molar extinction coefficients, high phototherapy efficacy, and excellent photostability. After being formed into nanostructures, BODIPY-containing nano-photosensitizers show enhanced water solubility and biocompatibility as well as efficient tumor accumulation compared to BODIPY molecules. Hence, BODIPY nano-photosensitizers demonstrate a promising potential for fighting cancer. This review contains three sections, classifying photodynamic therapy (PDT), photothermal therapy (PTT), and the combination of PDT and PTT based on BODIPY nano-photosensitizers. It summarizes various BODIPY nano-photosensitizers, which are prepared via different approaches including molecular precipitation, supramolecular interactions, and polymer encapsulation. In each section, the design strategies and working principles of these BODIPY nano-photosensitizers are highlighted. In addition, the detailed in vitro and in vivo applications of these recently developed nano-photosensitizers are discussed together with future challenges in this field, highlighting the potential of these promising nanoagents for new tumor phototherapies.

Nanoscale Metal-Organic Frameworks for Phototherapy of Cancer.

Phototherapy involves the irradiation of tissues with light, and is commonly implemented in the forms of photodynamic therapy (PDT) and photothermal therapy (PTT). Photosensitizers (PSs) are often needed to improve the efficacy and selectivity of phototherapy via enhanced singlet oxygen generation in PDT and photothermal responses in PTT. In both cases, efficient and selective delivery of PSs to the diseased tissues is of paramount importance. Nanoscale metal-organic frameworks (nMOFs), a new class of hybrid materials built from metal connecting points and bridging ligands, have been examined as nanocarriers for drug delivery due to their compositional and structural tunability, highly porous structures, and good biocompatibility. This review summarizes recent advances on using nMOFs as nanoparticle PSs for applications in PDT and PTT.