Construction of CuS@Fe-MOF nanoplatforms for MRI-guided synergistic photothermal-chemo therapy of tumors

Abstract

Integrated theranostic nanoplatforms with imaging and photothermal/drug-delivering functions have great advantages in cancer therapy, but the design and preparation of the simple efficient nanoplatforms are still of great urgency. Herein, we report the construction of novel core-shell CuS@Fe-based metal-organic-framework (Fe-MOF) nanoplatforms by the co-precipitation/assembling growth of Fe-MOF shell on the surface of CuS nanoplate. The resulting CuS@Fe-MOF nanoparticles (NPs) consist of hexagonal-shaped CuS nanoplate core with an average size of ~85 nm and amorphous Fe-MOF shells with an average thickness of 16 nm. CuS@Fe-MOF NPs are then surface-modified with lipids, and they exhibit the increased NIR photoabsorption and photothermal conversion efficiency (39.7%), resulting from localized surface plasmon resonance (LSPR) effect of CuS. The presence of Fe-MOF shell confers the efficient loading (27.5%) of doxorubicin (DOX), pH-responsive releasing ability, and strong magnetic resonance imaging (MRI) ability. Especially, the photothermal effect of CuS and the released DOX from CuS@Fe-MOF-DOX result in the most efficient death of cancer cells in vitro. When CuS@Fe-MOF-DOX dispersion was injected into the tumor, the tumor-bearing mice could be monitored by MR and thermal imaging. Furthermore, the tumors could be inhibited and destroyed due to the synergistic photothermal-chemo therapy, remarkably better than that from photothermal ablation therapy or chemotherapy alone. Simultaneously, no noticeable side-effects can be found for mice. Therefore, the present CuS@Fe-MOF-DOX can act as a biocompatible multifunctional nanoplatform for MRI-guided synergistic photothermal-chemo therapy of tumors.