A copper–platinum nanoplatform for synergistic photothermal and chemodynamic tumor therapy via ROS outburst and GSH exhaustion

Abstract

A multifunctional nanoplatform is obtained by modifying copper hexacyanoferrate (Cu-HCF) nanozyme with hyaluronic acid (HA) and further loading platinum (Pt) nanoparticles. This Cu-HCF-HA@Pt platform shows peroxidase-like and glutathione oxidase-like dual-enzyme catalytic activities and photothermal properties, enabling synergistic chemodynamic and photothermal tumor therapy. HA binds to the CD44 receptor, which is highly expressed on the exterior surface of tumor cells, endowing the nanoplatform with tumor specificity. Cu-HCF-HA@Pt catalyzes the decomposition of H₂O₂ to produce abundant hydroxyl radicals within tumor cells, increasing intracellular oxidative stress levels and inducing tumor cell apoptosis. Meanwhile, Cu-HCF-HA@Pt catalyzes the conversion of intracellular reduced glutathione (GSH) to oxidized glutathione, resulting in GSH exhaustion. The conversion of Cu^II to Cu^I in Cu-HCF via a Fenton-like reaction can improve the peroxidase-like property of Cu-HCF-HA@Pt. After the probe is targeted to the tumor site, irradiation by an 808 nm near-infrared laser causes local heating and brings about photothermal tumor apoptosis when reaching 45 °C. The prepared Cu-HCF-HA@Pt combines nanozyme-catalyzed therapy with photothermal therapy to induce apoptosis in tumor cells.