Precise Design of Atomically Dispersed Fe, Pt Dinuclear Catalysts and Their Synergistic Application for Tumor Catalytic Therapy.

Recently, extending single-atom catalysts from mono- to binary sites has been proved to be a promising way to realize more efficient chemical catalytic processes. In this work, atomically dispersed Fe, Pt dinuclear catalysts ((Fe, Pt)SA-N-C) with an ca. 2.38 Šdistance for Fe1 (Fe-N3) and Pt1 (Pt-N4) could be precisely controlled via a novel secondary-doping strategy. In response to tumor microenvironments, the Fe-N3/Pt-N4 moieties exhibited synergistic catalytic performance for tumor catalytic therapy. Due to its beneficial microstructure and abundant active sites, the Fe-N3 moiety effectively initiated the intratumoral Fenton-like reaction to release a large amount of toxic hydroxyl radicals (•OH), which further induced tumor cell apoptosis. Meanwhile, the bonded Pt-N4 moiety could also enhance the Fenton-like activity of the Fe-N3 moiety up to 128.8% by modulating the 3d electronic orbitals of isolated Fe-N3 sites. In addition, the existence of amorphous carbon revealed high photothermal conversion efficiency when exposed to an 808 nm laser, which synergistically achieved an effective oncotherapy outcome. Therefore, the as-obtained (Fe, Pt)SA-N-C-FA-PEG has promising potential in the bio-nanomedicine field for inhibiting tumor cell growth in vitro and in vivo.

A flowerlike FePt/MnO2/GOx-based cascade nanoreactor with sustainable O2 supply for synergistic starvation-chemodynamic anticancer therapy.

The development of versatile nanotheranostic agents has received increasing interest in cancer treatment. Herein, in this study, we rationally designed and prepared a novel flowerlike multifunctional cascade nanoreactor, BSA-GOx@MnO2@FePt (BGMFP), by integrating glucose oxidase (GOx), manganese dioxide (MnO2) and FePt for synergetic cancer treatment with satisfying therapeutic efficiency. In an acidic environment, intratumoral H2O2 could be decomposed to O2 to accelerate the consumption of glucose catalyzed by GOx to induce cancer starvation. Moreover, the accumulation of gluconic acid and H2O2 generated along with the consumption of glucose would in turn promote the catalytic efficiency of MnO2 and boost O2 evolution, which could enhance the efficiency of starvation therapy. Moreover, FePt as an excellent Fenton agent could simultaneously convert H2O2 to the toxic hydroxyl radical (˙OH), subsequently resulting in amplified intracellular oxidative stress and cell apoptosis. Therefore, BGMFP could catalyze a cascade of intracellular biochemical reactions and optimize the unique properties of MnO2, GOx and FePt via mutual promotion of each other to realize O2 supply, chemodynamic therapy (CDT) and starvation therapy. The anticancer results in vitro and in vivo demonstrated that BGMFP possessed remarkable tumor inhibition capacity through enhancing the starvation therapy and CDT. It is appreciated that BGMFP could be a promising platform for synergetic cancer treatment.