Tetramodal Imaging and Synergistic Cancer Radio-Chemotherapy Enabled by Multiple Components-Encapsulated Zeolitic Imidazolate Frameworks.

The abundant species of functional nanomaterials have attracted tremendous interests as components to construct multifunctional composites for cancer theranostics. However, their distinct chemical properties substantially require a specific strategy to integrate them in harmony. Here, we report the preparing of a distinctive multifunctional composite by encapsulating small-size semiconducting copper bismuth sulfide (CBS) nanoparticles and rare-earth down-conversion (DC) nanoparticles in larger-size zeolitic imidazolate framework-8 (ZIF8) nanoparticles, followed by the loading of an anticancer drug, doxorubicin (DOX). Such composites can be used for tetramodal imaging, including traditional computed tomography and magnetic resonance imaging and recently emerged photoacoustic imaging and fluorescence imaging. Besides, with a pH-responsive release of the encapsulated components, synergistic radio-chemotherapy with a high (87.6%) tumor inhibition efficiency is achieved at moderate doses of CBS&DC-ZIF8@DOX composite and X-ray irradiation. This promising strategy highlights the extending capacity of zeolitic imidazolate frameworks to encapsulate multiple distinct components for enhanced cancer imaging and therapy.