Design of enzyme nanoreactor by phase-transitioned lysozyme modified magnetic dendritic silica nanoparticle for efficient catalytic performance at harsh reaction condition.

[Display omitted] • Efficient bio-nanoreactor constructed by modified core–shell magnetic dendritic silica (MDSP). • Phase-transitioned lysozyme (PTL) covered around MDSP plays multiple roles. • The matching of channel in MDSP with CPO size avoid aggregation of CPO. • Magnetic separation instead of centrifugation greatly decrease the loss of the material in reuse. • The bio-nanoreactor is very effective in degradation of antibiotic residues (nofloxacin). Immobilization of enzyme on porous solid nanosupport is an effective way to improve its stability. In this work, core–shell magnetic dendritic silica nanoparticle (MDSP) is prepared for encapsulation of chloroperoxidase (CPO). Amyloid like proteins formed by phase-transitioned lysozyme(PTL) is covered around CPO@MDSP to hold another layer of CPO (CPO@PTL-CPO@MDSP). CPO@PTL-CPO@MDSP is very stable at high temperature and in the presence of organic solvent. 91.3 % of catalytic activity at 80 °C is remained compared to 37.5 % of free enzyme. 78.2 % of original activity are retained in the presence of 30 % methanol, while the free enzyme can only keep 13.5 % of activity. CPO@PTL-CPO@MDSP can remain 77.0 % of the original catalytic activity remained after 24 cycles. In the application on the degradation of norfloxacin, 95.2 % of degradation efficiency is achieved in 20 min. This work provides a universal platform for the design of enzyme nanoreactor suitable for industrial application. [ABSTRACT FROM AUTHOR]