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The combination of noble metal and oxide support is a good approach to reduce the cost of noble metal catalyst and improve the stability of nanocatalyst in chemical reactions. Here, noble metal/zinc oxide composites, including Pd/ZnO and Pt/ZnO, have been facilely prepared through the general one-pot hydrothermal method. Importantly, the morphology of composites can be tuned from tube, flower, and star to skin needling-like shapes by easily adjusting the alkalinity of the reaction solution. By investigating the growth mechanism and influencing factors of the morphology of noble metal/zinc oxide composites, the differences of the morphology of composites can be ascribed to various growing units and directions of ZnO crystal under different alkalinities. Among them, Pd/ZnO composites exhibited both higher catalytic activity and excellent stability in the Suzuki coupling reaction between iodobenzene and phenylboronic acid and the reduction of 4-nitrophenol to 4-aminophenol by sodium borohydride. Such supported composites will potentially be used as green and sustainable catalysts for many chemical reactions.

Chemodynamic therapy (CDT) is an emerging tumor treatment; however, it is hindered by insufficient endogenous hydrogen peroxide (H2O2) and high glutathione (GSH) concentrations in the tumor microenvironment (TME). Furthermore, CDT has limited therapeutic efficacy as a monotherapy. To overcome these limitations, in this study, a nanoplatform is designed and constructed from Cu-doped mesoporous Prussian blue (CMPB)-encapsulated glucose oxidase (GOx) with a coating of hyaluronic acid (HA) modified with a nitric oxide donor (HN). In the proposed GOx@CMPB-HN nanoparticles, the dopant Cu2+ions are crucial to combining and mutually promoting multiple therapeutic approaches, namely, CDT, photothermal therapy (PTT), and starvation therapy. The dopant Cu2+ions in CMPB protect against reactive oxygen species to deplete the intracellular GSH in the TME. Additionally, the byproduct Cu+ions act as a substrate for a Fenton-like reaction that activates CDT. Moreover, H2O2, which is another important substrate, is produced in large quantities through intracellular glucose depletion caused by the nanoparticle-loaded GOx, and the gluconic acid produced in this reaction further enhances the TME acidity and creates a better catalytic environment for CDT. In addition, Cu2+doping greatly improves the mesoporous Prussian blue (MPB) photothermal conversion performance, and the resultant increase in temperature accelerates CDT catalysis. Finally, the HN coating enables the nanoparticles to actively target CD44 receptors in cancer cells and also enhances vascular permeability. Therefore, this coating has multiple effects, such as facilitating enhanced permeability and retention and deep laser penetration. In vitro and in vivo experiments demonstrate that the proposed GOx@CMPB-HN nanoplatform significantly inhibits tumor growth with the help of in situ enhanced synergistic therapies based on the properties of the TME. The developed nanoplatform has the potential to be applied to cancer treatment and introduces new avenues for tumor treatment research.

Novel nanomaterials and advanced nanotechnologies prompt the fast development of new protocols for biomedical application. The unique light-to-heat conversion property of nanoscale materials can be utilized to produce novel and effective therapeutics for cancer treatment. In particular, near-infrared (NIR) photothermal therapy (PTT) has gained popularity and very quickly developed in recent years due to minimally invasive treatments for patients. This review summarizes the current state-of-the-art in the development of inorganic nanocomposites for photothermal cancer therapy. The current states of the design, synthesis, the cellular uptake behavior, the cellular cytotoxicity and both in vivoand in vitronanoparticle assisted photothermal treatments of inorganic photothermal therapy agents (PTA) are described. Finally, the perspective and challenges of PTT development are presented and some proposals are suggested for its further development and exploration. This summary should provide improved understanding of cancer treatment with photothermal nanomaterials and push nanoscience and nanotechnology one step at a time toward clinical applications.