Synergizing Nanozyme-Enzymes Catalytic Cascade by Spatial Segregation in a Hollow MOF Microreactor.

The integration of enzyme-nanozyme cascades presents a powerful route for diversifying catalytic conversions, yet its potential is often limited by mutual inactivation and mass transfer constraints. Here, we report a spatial compartmentalized core-shell microreactor to overcome these challenges using a metal-organic framework (MOF) hollowing and heterometallation strategy. The resulting MOF cascade microreactor features a "dynamic" core (enzyme)-"static" shell (nanozyme) nanoarchitecture. This hierarchical nano-architectonics not only mitigates diffusion limitations and keeps enzyme in a high freedom state but, more critically, shields the enzyme from deactivation by reactive oxygen species generated at the nanozyme shell. The resulting microreactor exhibits a 5.25-fold enhancement in cascade efficiency over its solid co-localized counterpart and a 1.95-fold increase over a co-localized hollow system. We demonstrate the general adaptability of this approach with multiple oxidases and leverage the catalytic cascade principle to construct a portable hydrogel-based glucose sensor with smartphone readout, achieving high sensitivity and stability for point-of-care testing. This work establishes rational spatial compartmentalization as a critical principle for developing efficient and durable enzyme-abiotic catalyst hybrids.