Ionic liquids-modified cellulose coated magnetic nanoparticles for enzyme immobilization: Improvement of catalytic performance.

In this work, ionic liquids-modified magnetic carboxymethyl cellulose nanoparticles (IL-MCMC) were prepared and used as supports for enzyme immobilization. The specific activity of immobilized lipase PPL-IL-MCMC was 1.43 and 2.81 folds higher than that of free PPL and PPL-MCMC, respectively. Water contact angle analysis indicated that the introduction of ionic liquids increased the hydrophobicity of supports, which in tune induced the lid-opening of lipase, allowing its active sites to become more accessible. In addition, the affinity between lipase and substrate immobilized on the prepared supports was enhanced. The same method was also applied to analyze immobilize penicillin G acylase (PGA) to further investigate the general applicability of the method. The results showed that the immobilized PGA exhibited higher stability than many other reported PGAs. The developed composites may be utilized as excellent supports for enzyme immobilization in industrial application.