Construction of degradable liposome-templated microporous metal-organic frameworks with commodious space for enzymes

The construction of enzyme reactors based on metal-organic frameworks (MOFs) as the immobilized matrix is a proven strategy that has achieved the widespread application of enzymes across industries. Although many MOFs and a variety of strategies have been developed, a formidable challenge remains in maintaining the high enzyme activity with excellent recyclability and tolerance for harsh conditions. Herein, using degradable redox stimuli-responsive liposomes as the templates with microporous MOFs (M-MOFs) as the hosts for enzyme encapsulation, a series of enzyme reactors (enzyme@M-MOFs) was designed and created. Based on the premise of enhancing enzyme protection in the harsh environment, this strategy provided a high degree-of-freedom space via removal of liposomes that improved the conformational freedom of the enzymes, promoted the mass transfer of substrates and products, and greatly boosted the catalytic activity. Importantly, the strategy had good universality and was applied to various liposomes, M-MOFs and enzymes. Additionally, the co-encapsulation of different enzymes with synergistic functions was performed using the M-MOFs platform. This study solved the problems of the conformation limitation of enzymes and mass transfer resistance of substrates and products using the proposed enzyme@M-MOFs, providing a new approach for the construction of biological cascade reaction devices based on MOFs materials.