Constructing biocatalytic nanochannel membranes for unidirectional isomer conversion and separation

Isomer conversion and separation are crucial in the chemical, pharmaceutical, and food industries. However, this process remains challenging due to the reversed conversion of isomers and their similar boiling points and kinetic diameters. Herein, an enzyme-catalyzed nanochannel membrane with a hierarchical structure is fabricated for selective and directional isomeric conversion and separation. The enzyme is embedded in a confined polymer network that shows high stability and retains 95% of its initial activity after 50 reaction cycles. Studying the transport mechanisms between isomers through the membrane shows that the hierarchical layers of the membrane impose unequal energy barriers to the forward and backward transport of products, promoting unidirectional diffusion of products and interrupting the equilibrium of the isomerization reaction to increase the conversion rate by 43%. Overall, this work opens a new avenue for the design of biocatalytic nanochannel membranes and the directional production and in situ separation of isomers.