Synergistic Regulation of Dynamic Hydrogen Bonds and Confinement Effects Enhancing Immobilized Enzyme Activity for Sustainable Enantioselective Catalysis

Immobilizing fragile enzymes within solid supports such as metal–organic frameworks (MOFs) enhances stability but often reduces catalytic activity due to mass transfer limitations and confinement. Herein, we propose an engineering strategy combining dynamic hydrogen-bonding (DHB) networks with confinement catalytic effects using carboxymethyl-β-cyclodextrin (CD)-functionalized macroporous UiO-66-NH2 (UiOm) for enhancing both stability and activity of immobilized enzymes. The DHB network, formed between CD hydroxyl groups and the enzyme, provides an interfacial flexibility to improve stability. Simultaneously, the combined rigid macroporous UiOm structure and flexible CD precisely regulate enzyme orientation within the confinement space. This dual approach enhances substrate enrichment and mass transfer efficiency, ensuring effective enzyme–media communication. This synergistic mechanism creates highly accessible catalytic centers, resulting in immobilized enzymes with 1.5∼7.0-fold higher activity than their free enzymes. The PS@UiOm-CD (immobilized Lipase PS) system exhibits excellent tolerance to harsh conditions (organic solvents, elevated temperatures) compared to both free enzymes and nonfunctionalized PS@UiOm. Immobilized enzymes with good catalytic activity were applied to enantioselective hydrolysis and transesterification reactions with an approximately 100% yield of single enantiomer and 100% enantiomeric excess. Furthermore, the feasibility and versatility of this synergistic strategy have been validated through the successful immobilization of various enzyme types.