Initiator‐Loaded Gold Nanocages as a Light‐Induced Free‐Radical Generator for Cancer Therapy

Abstract

Tumor hypoxia greatly suppresses the therapeutic efficacy of photodynamic therapy (PDT), mainly because the generation of toxic reactive oxygen species (ROS) in PDT is highly oxygen-dependent. In contrast to ROS, the generation of oxygen-irrelevant free radicals is oxygen-independent. A new therapeutic strategy based on the light-induced generation of free radicals for cancer therapy is reported. Initiator-loaded gold nanocages (AuNCs) as the free-radical generator were synthesized. Under near-infrared light (NIR) irradiation, the plasmonic heating effect of AuNCs can induce the decomposition of the initiator to generate alkyl radicals (R ), which can elevate oxidative-stress (OS) and cause DNA damages in cancer cells, and finally lead to apoptotic cell death under different oxygen tensions. As a proof of concept, this research opens up a new field to use various free radicals for cancer therapy.

Photoactivated Trifunctional Platinum Nanobiotics for Precise Synergism of Multiple Antibacterial Modes

“…Many reports claimed that metal NPs were capable of elevating the concentration of active oxygen molecules in bacteria and thus resulted in apoptosis and death . Besides, photodynamic effect was another approach involved in ROS metabolism Hence, rhodamine B, a dye vulnerable to fading because of oxidation, was used in this experiment. Without NIR irradiation, the areas under ultraviolet absorption curves (AUC) of all subject groups remained at baseline (Figure S10, Supporting Information).…”

Multifunctional Nanotherapeutics for Photothermal Combination Therapy of Cancer

“…[82] In their design, an azo compound is loaded to the hollow cavity of gold nanocages and lauric acid (melting point 44°C) is used to fix the azo compound inside the nanocages (Figure 5c). [83] In fact, application of phase change materials with low melting points as a switch to control the release of cargoes has been previously reported for a photothermal-triggered release of anticancer drugs. The alkyl radicals have very high cytotoxicity and can be used to kill cancer cells.…”

“…Reproduced with permission. [83] Copyright 2017, Wiley-VCH. c) Schematic illustration showing the controlled release and generation of free radicals upon irradiation by a NIR laser.…”

Activation of Prodrugs by NIR‐Triggered Release of Exogenous Enzymes for Locoregional Chemo‐photothermal Therapy

“…[11] Under NIR laser irradiation, plasmonic photothermal agents can convert the absorbed optical energy into heat by the Landau damping effect to controllably release the content. [11] Under NIR laser irradiation, plasmonic photothermal agents can convert the absorbed optical energy into heat by the Landau damping effect to controllably release the content.…”