Fe-salphen complexes from intracellular pH-triggered degradation of Fe3O4@Salphen-InIII CPPs for selectively killing cancer cells

We propose a modular synthetic strategy to constitute metallosalphen prodrugs in the form of coordination polymer nanoparticles, comprising magnetite nanocrystal colloidal cluster as core and salphen-InIII coordination polymer as shell. These composite nanoparticles are not only equipped with intense photoluminescence, sensitive magnetic responsiveness and pH-dependent degradability, but also serve as prodrugs to accomplish intercellular conversion from non-toxic nanoparticles (Fe3O4@Salphen-InIII) to pharmacologically active complexes (Fe-salphen), allowing to specifically inhibit the proliferation of A549 cancer cells via caspase activation.