Confined Catalysis of Enzymes: Enhancement Strategies, Materials, and Biosensor Applications.

Confined catalysis enhances enzyme activity, stability, and selectivity by encapsulating enzymes in well-defined micro- or nanoscale environments. Unlike conventional immobilization strategies, which primarily stabilize enzymes, this approach actively regulates enzyme behavior, substrate transport, and product removal, addressing challenges in real-world biosensing. In this work, we connect confined catalysis principles with biosensor design requirements, emphasizing tailored microenvironments, hierarchical pore architectures, and cascade reaction optimization to improve sensitivity, selectivity, and operational stability. The review also highlights advanced strategies such as molecular imprinting, aptamer recognition, and DNA scaffold-guided co-localization, which enable precise substrate discrimination and efficient signal amplification. By integrating these confinement strategies with emerging materials, including biological macromolecular materials, amorphous porous materials, and crystalline framework materials, this work outlines pathways to next-generation biosensors with enhanced performance and practical applicability, addressing limitations overlooked in previous studies.