Ferrocene Functionalized Upconversion Nanoparticle Nanosystem with Efficient Near-Infrared-Light-Promoted Fenton-Like Reaction for Tumor Growth Suppression

Abstract

By taking advantage of the efficient Förster resonance energy transfer (FRET) between near-infrared (NIR)-responsive lanthanide-doped upconversion nanoparticles (UCNPs) and Fenton reagent ferrocenyl compounds (<b>Fc</b>), a series of <b>Fc</b>-UCNPs was designed by functionalizing NaYF₄:Yb,Tm nanoparticles with <b>Fc1</b>-<b>Fc5</b> <i>via</i> surface-coordination chemistry. <b>Fc</b>-UCNP-Lipo nanosystems were then constructed by encapsulating <b>Fc</b>-UCNP inside liposomes for efficient delivery. <b>Fc</b>-UCNP can effectively release ·OH <i>via</i> a NIR-promoted Fenton-like reaction. <i>In vitro</i> and <i>in vivo</i> studies of <b>Fc1</b>-UCNP-Lipo confirmed the preferential accumulation in a tumor site followed by an enhanced uptake of cancer cells. After cellular internalization, the released <b>Fc1</b>-UCNP can effectively promote ·OH generation for tumor growth suppression. Such a <b>Fc1</b>-UCNP-Lipo nanosystem exhibits advantages such as easy fabrication, low drug dosage, and no ferrous ion release.