High Biocompatible ZIF-8 Coated by ZrO₂ for Chemo-microwave Thermal Tumor Synergistic Therapy

The zeolitic imidazolate framework-8 (ZIF-8) is a specifically promising drug carrier due to its excellent intrinsic properties. However, the high toxicity of ZIF-8 nanoparticles severely limits their further research and clinical application. In this work, the biocompatibility of ZIF-8 nanoparticles is greatly improved by coating ZrO₂ onto the surface. The survival rate of cells and mice in the ZIF-8@ZrO₂ nanocomposite group is significantly increased compared with the undecorated ZIF-8 nanoparticle group. Doxorubicin (DOX) as a chemotherapeutic drug is deposited during the ZIF-8 growth by a facile one-pot method. Ionic liquid (IL) is loaded into the pore of the ZIF-8/DOX@ZrO₂ nanocomposites for enhancing microwave thermal therapy. The tumor inhibition rate of ZIF-8/DOX@ZrO₂@IL nanocomposites with synergistic microwave thermal therapy and chemotherapy is obviously higher than in other groups. In addition, the ZIF-8/DOX@ZrO₂@IL nanocomposites are used for real-time monitoring of the therapeutic outcomes due to the excellent computed tomography contrast agent, ZrO₂. Therefore, such a ZrO₂ coating strategy shows great promise for overcoming high toxicity of ZIF-8 nanoparticles, which offers a new platform for tumor synergistic microwave thermal therapy and chemotherapy using the ZIF-8/DOX@ZrO₂@IL nanocomposite as a theranostic nanocarrier.