Tumor Microenvironment-Responsive Biodegradable Nanomedicine for Self-Enhanced Synergistic Chemo-, Photothermal, and Chemodynamic Therapy

The nanoscale multidrug codelivery system for synergistic therapy is an effective strategy for tumor treatment. However, the low drug delivery efficiency and poor therapeutic effects limit its application. Here, based on the coordination effect of Artemisinin (Art), quercetin (Qc), and Fe³⁺, we had constructed a safe and efficient carrier-free hyaluronic acid (HA)-modified Art-Fe-Qc nanoparticles (AFQ@HA NPs) for enhanced chemotherapy/photothermal therapy (PTT)-chemodynamic therapy (CDT) synergistic therapy, which achieved an ultrahigh drug loading efficiency and a multifunction anticancer strategy. The results showed that high drug loading was achieved based on drug coordination self-assembly, with Art and Qc contents of 38.6 and 42.7%, respectively. At the same time, based on the Qc-Fe coordination molecular network, the system had excellent photothermal conversion performance with an efficiency of 57.3% and could effectively inhibit the expression of HSP70, achieving enhanced PTT. Further, under the stimulation of excessive H₂O₂ and glutathione (GSH) in the tumor microenvironment, the AFQ@HA NPs were continuously degraded, while releasing Art and Fe³⁺/Fe²⁺ to achieve iron ion-enhanced CDT. The results of in vitro and in vivo experiments showed that AFQ@HA NPs could achieve chemotherapy-PTT-CDT synergistic therapy in response to tumor microenvironment by passively targeting and actively targeting tumor cells with CD44, demonstrating its excellent targeted antitumor effects.