Mesoporous porphyrinic metal-organic framework nanoparticles/3D nanofibrous scaffold as a versatile platform for bone tumor therapy

Removal of residual tumor cells and regeneration of large bone defects are urgently required after surgical resection of bone tumors. To address these issues, a bifunctional scaffold with high photothermal effect and osteogenesis was developed for bone tumor therapy. Sintered mesoporous imidazolate framework 8 (ZIF8) nanoparticles with porphyrin-like macrocycles were synthesized by calcination of ZIF8 precursors under an N2 atmosphere. The prepared ZIF8 possesses good photothermal efficacy and drug loading capability. Phenamil (Phe), an activator of bone morphogenetic protein pathways, was encapsulated into ZIF8 before loading onto gelatin nanofibrous (GF) scaffolds. The loaded Phe exhibited sustained and near-infrared triggered release profiles, which is capable of promoting bone morphogenetic protein 2 induced osteogenic differentiation even under near-infrared treatment. Moreover, our studies revealed that the photothermal effect of GF/ZIF8-Phe scaffolds can kill MG-63 cells in vitro and inhibit subcutaneous tumor growth in vivo. Therefore, the GF/ZIF8-Phe scaffold represents a novel bifunctional platform for tumor therapy and bone regeneration.