A combination of tri-modal cancer imaging and in vivo drug delivery by metal-organic framework based composite nanoparticles.

Multifunctional Fe3O4@polyacrylic acid/Au nanoclusters/zeolitic imidazolate framework-8 nanoparticles (Fe3O4@PAA/AuNCs/ZIF-8 NPs) integrating tri-modal cancer imaging (magnetic resonance, computed X-ray tomography and fluorescence imaging) and chemotherapy into a single system were fabricated by using a facile, mild and reproducible strategy. The obtained NPs possess many merits including ultrahigh doxorubicin (DOX) loading capability (1.54 mg DOX per mg NPs), dual pH-responsive controlled drug release, tri-modal cancer imaging ability, facile magnetic separation and good biocompatibility. Importantly, the NPs exhibit low systematic toxicity and high antitumor therapy efficacy in vivo through tail vein injection. Furthermore, the achievement of in vitro tri-modal cancer cell imaging reveals the potential of Fe3O4@PAA/AuNCs/ZIF-8 NPs for cancer diagnosis and visualized-synergistic therapy. Taken together, Fe3O4@PAA/AuNCs/ZIF-8 NPs can be developed as a promising theranostic agent that combines multiple capabilities for cancer treatment.