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 Å distance 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.
Keywords: atomically dispersed; cancer treatment; dinuclear catalysts; photothermal therapy; reactive oxygen species.