Precision Treatment of Colon Cancer Using Doxorubicin-Loaded Metal–Organic-Framework-Coated Magnetic Nanoparticles

Due to the limited efficacy and evident side effects of traditional chemotherapy drugs attributed to their lack of specificity and selectivity, novel strategies are essential for improving cancer treatment outcomes. Here, we successfully engineered Fe₃O₄ magnetic nanoparticles coated with zeolitic imidazolate framework-8 (ZIF-8). The resulting nanocomposite (Fe₃O₄@ZIF-8) demonstrates efficient adsorption of a substantial amount of doxorubicin (DOX) due to the porous nature of ZIF-8. The drug-loaded nanoparticles, Fe₃O₄@ZIF-8/DOX, exhibit significant accumulation at the tumor site in SW620 colon-cancer-bearing mice when guided by an external magnetic field. Within the acidic microenvironment of the tumor, the ZIF-8 framework collapses, releasing DOX and effectively inducing tumor cell death, thereby inhibiting cancer progression while not causing undesired side effects, as confirmed by a variety of in vitro and in vivo characterizations. In comparison to free DOX, Fe₃O₄@ZIF-8/DOX nanoparticles show superior efficacy in colon cancer treatment. Our findings suggest that Fe₃O₄@ZIF-8 holds promise as a carrier for small-molecule drug adsorption and its ferromagnetic properties provide drug targeting capabilities, thereby enhancing therapeutic effects on tumors at the same drug dosage. With excellent biocompatibility, Fe₃O₄@ZIF-8 demonstrates potential as a drug carrier in targeted cancer chemotherapy. Our work suggests that a combination of magnetic targeting and acid-responsiveness holds great promise for advancing targeted cancer therapy in precision nanomedicine.