Biomimetic Permselective Membranes Tailoring Multidimensionally Regulated Microenvironments for Enhanced Enzyme Cascade Catalysis

In multienzyme cascade systems, overall efficiency is often limited by the uncontrolled diffusion and dilution of substrates and intermediates in bulk solution. Inspired by the cooperative roles of hydrated cellular compartments and selectively permeable membranes, we report a biomimetic enzyme immobilization strategy based on a hollow microsphere with a multidimensionally permselective membrane to regulate mass transfer and sustain an efficient reaction microenvironment. The membrane, composed of charged polyelectrolytes, serves as a dynamic soft interface, enabling cooperative transport regulation through apparent size-selective retention and electrostatic interactions. Furthermore, a three-enzyme cascade reaction demonstrates that tuning the surface charge drives self-assembly of compartmentalized microspheres. The proximity-enhanced assembly reduces intermediate diffusion distances, thereby enhancing cascade activity. This work establishes a membrane-mimetic design strategy based on polyelectrolyte soft interfaces, providing a modular platform for constructing biomimetic catalytic systems and offering insights for rational engineering of multicompartmental artificial cells.