Regular articleRegulation of enzyme activity and stability through positional interaction with polyurethane nanofibers

•Both solid and hollow nanofibers were used for CT immobilization.•Catalytic kinetics of CT immobilized through different methods was investigated.•CT encapsulated in hollow nanofibers showed the highest catalytic efficiency.•The confinement effect of hollow nanofibers enhanced the enzymes stability.

Nanofibrous membranes have been adopted as enzyme carriers via surface adsorption, covalent cross-linking, and direct electrospinning-embedment showing great advantages and successes over other nanostructured materials, and especially the newly developed hollow nanofibers were proven as an ideal scaffold for through in-situ encapsulation of multiple enzymes during co-axial electrospinning. Here, the coaxial electrospinning-encapsulation method based on hollow nanofiber structures, together with three previous strategies, which are all based on solid-structured nanofibers, were adopted to immobilize α-chymotrypsin (CT). The feasibilities and advantages of hollow nanofibers encapsulated enzyme are fully demonstrated by the catalytic kinetics of the immobilized CT for hydrolysis and transesterification. Compared to a solid nanofibers-based enzyme, the hollow nanofibers encapsulated CT show the highest catalytic efficiency for both hydrolysis and transesterification. Besides, the confinement effect provided by the nano-scaled hollow chamber not only facilitated molecular interactions between enzymes and substrates, but also enhanced the enzymes stability largely.