(727e) Immobilization and Stabilization of Carbonic Anhydrase into Magnetic Mesoporous Silica Via Crosslinked Chitosan Coating

Enzymes are biocatalysts that can be used for various applications such as microbial decontamination, biosensors, biofuel cells, enzyme-linked immunosorbent assay (ELISA) and CO₂ conversion and utilization. However, their practical success in various applications are hampered by the poor enzyme stability. In the present work, we used magnetically-separable spherical mesocellular siliceous foam (Mag-S-MCF) for the immobilization and stabilization of carbonic anhydrase (CA) via a new protocol of crosslinked chitosan (CS) coating. CA was adsorbed into Mag-S-MCF. Then, chitosan was adsorbed onto the surface of Mag-S-MCF with pre-adsorbed CA, and further crosslinked via the glutaraldehyde treatment. The crosslinked chitosan coating could effectively prevent the leaching of enzyme molecules, showing no decrease of CA activity under shaking (200 rpm) for 78 days. It also showed no activity decrease under recycled uses via facile magnetic separation. This new protocol of crosslinked chitosan on porous materials with pre-adsorbed enzymes has a great potential to be used for the various enzyme applications, where the poor enzyme stability inhibits their practical applications.