An Unprecedented FeMo6@Ce-Uio-66 Nanocomposite with Cascade Enzyme-Mimic Activity as Colorimetric Sensing Platform

Introducing the idea of integrated design and cascade activity into nanozyme, the novel integrated nanozymes (INAzymes), FeMo6@Ce-Uio-66 (FC-66(n)), were designed and synthesized by encapsulating iron-based polyoxometalates (FeMo6) into the ceria-based metal-organic framework (Ce-Uio-66). Due to the oxygen-driven reversible Ce3+/Ce4+ couple sites, the Fenton-like effect by iron centers, the nanoscale proximity effects by nanocages, and their synergistic effects, FC-66(n) as INAzymes exhibit elegant cascade enzyme-mimic activities (oxidase-, peroxidase-, and Fenton-like activity), which realizes INAzyme activities based on polyoxometalates based metal-organic framework (POMOFs). By employing dopamine (DA) detection as a model reaction, a high-efficient fluorescent turning-on-enhanced platform under near neutral conditions was established.

Automated summary

In this study, novel integrated nanozymes (INAzymes) were designed and synthesized by encapsulating iron-based polyoxometalates into a ceria-based metal-organic framework. The INAzymes exhibit elegant cascade enzyme-mimic activities and a high-efficient fluorescent turning-on-enhanced platform for dopamine detection was established.