Efficient immobilization of firefly luciferase in a metal organic framework: Fe-MIL-88(NH2) as a mighty support for this purpose

We investigated the mechanism of luciferase immobilization on a solid surface through therphtalaldehyde in order to understand the role of this linker on stability and activity of luciferase. Metal organic frameworks (MOFs) are capable supports for the stabilization of some proteins and biomolecules, therefore, in this context for the first time, we report a light emmiting enzyme immobillization on one of these supports and then outline chemical developments in this process. To this end, Fe-MIL-88(NH2) was used to immobilize native luciferase and therphtalaldehyde linker was attached to the framework as an activated group. Interestingly, high loading capacity was observed in both bonding mechanisms. Furthermore, thermal stability and kinetic properties were improved very much but, thermodynamic/kinetic results and bonding efficiency is much better in the modified-MOF than native MOF. It was found that Schiff base mechanism between aldehyde as an active functional group in MOF and amine groups of enzyme led to the formation of imine bond. The surface chemical structure and morphologies of Fe-MIL-88(NH2) were characterized by FTIR, X-ray diffraction, Brunauer–Emmett–Teller (BET), FE-SEM, and TEM. In conclusion, using Fe-MIL-88(NH2) as a support to immobilize luciferase established simple immobilization process of luciferase with and without linker and it improved the remaining activity significantly.