Zeolitic imidazolate frameworks-based nanomaterials for biosensing, cancer imaging and phototheranostics

Abstract Nanoscaled metal organic frameworks have emerged as a novel type of organic-inorganic hybrid coordination polymeric nanomaterials and showed great promise in biomedical area in recent decades. As a special subclass, zeolitic imidazolate frameworks (ZIFs), constructing with metal ions and imidazolate linkers, own unique advantages of high porosity, large surface area, good biocompatibility, pH sensitivity and etc. These render ZIFs as attractive and promising platforms to delivery various cargos of drugs, imaging probes and biomacromolecules for cancer diagnosis and therapy. And this review specially summaries the state-of-the-art research on ZIFs for biosensing, cancer imaging and phototheranostics within the latest 5 years. The multiply strategies of synthesis, characterization and functionalization of ZIFs-based nanosystems are firstly discussed. The vital roles of ZIFs in biosensors, including electrochemical, fluorescent and colorimetric sensors are analyzed. Then, the monomodal and/or multimodal cancer imaging techniques mediated by ZIFs are addressed. Particular emphasis is placed on the ZIFs-based cancer phototheranostics which provide a potential alternative avenue to greatly improve the therapeutic index of cancer. Finally, the future opportunities and challenges of ZIFs are tentatively proposed and discussed from the point of translational medicine.