Design of epoxy-functionalized Fe3O4@MCM-41 core-shell nanoparticles for enzyme immobilization

The scope of our research was to prepare the organosilane-modified Fe3O4@MCM-41 core-shell magnetic nano particles, used for L-ASNase immobilization and explored screening of immobilization conditions such as pH, temperature, thermal stability, kinetic parameters, reusability and storage stability. In this content, Fe3O4 core shell magnetic nanoparticles were prepared via co-precipitation method and coated with MCM-41. Then, Fe3O4@MCM-41 magnetic nanoparticles were functionalized by (3-glycidyloxypropyl) trimethoxysilane (GPTMS) as an organosilane compound. Subsequently, L-ASNase was covalently immobilized on epoxyfunctionalized Fe3O4@MCM-41 magnetic nanoparticles. The immobilized L-ASNase had greater activity at high pH and temperature values. It also maintained >92% of the initial activity after incubation at 55 degrees C for 3 h. Regarding kinetic values, immobilized L-ASNase showed a higher Vmax and lower Km compared to native L-ASNase. In addition, it displayed excellent reusability for 12 successive cycles. After 30 days of storage at 4 degrees C and 25 degrees C, immobilized L-ASNase retained 54% and 26% of its initial activities while native L-ASNase lost about 68% and 84% of its initial activity, respectively. As a result, the immobilization of L-ASNase onto magnetic nanoparticles may provide an advantage in terms of removal of L-ASNase from reaction media. (C) 2018 Elsevier B.V. All rights reserved.