Enhancing bio-catalytic performance of lipase immobilized on ionic liquids modified magnetic polydopamine

In this study, imidazolium-based ionic liquid with [tf2N]- as the anion was successfully grafted to magnetic polydopamine nanoparticles (MPDA). The prepared materials were well characterized and used as supports for lipase immobilization. The immobilized lipase (PPL-ILs-MPDA) exhibited excellent activity and stability. The specific activity of PPL-ILs-MPDA was 2.15 and 1.49 folds higher than that of free PPL and PPL-MPDA. In addition, after 10 rounds of reuse, the residual activity of PPL-ILs-MPDA was 86.2 % higher than that of PPLMPDA (75.4 %). Furthermore, the kinetic assay indicated that the affinity between PPL-ILs-MPDA and substrate had increased. Analysis of the secondary structure using circular dichroism was used to explain the mechanism underlying the improvement in the performance of PPL-ILs-MPDA. In addition, the immobilized lipase can be easily separated from the reaction system with a magnet. The observations regarding the development of new supports for lipase immobilization may provide new ideas regarding further studies in this field.

Automated summary

In this study, imidazolium-based ionic liquid was successfully grafted to magnetic polydopamine nanoparticles for lipase immobilization. The immobilized lipase showed excellent activity and stability, with increased affinity to substrate. Additionally, the immobilized lipase can be easily separated from the reaction system with a magnet, providing new ideas for further studies in this field.