NiFe2O4/polyhydroxymethyl methacrylate and Fe3O4/polyhydroxymethyl methacrylate magnetic nanogels for lipase immobilization

Abstract

In this study, the optimization and characterization of NiFe2O4/Polyhydroxymethyl methacrylate (NF-pHEMA) and Fe3O4/Polyhydroxymethyl methacrylate (M-pHEMA) magnetic nanogel structures were carried out and the usability of these magnetic nanogels for the immobilization of lipase enzyme was investigated. Fe3O4/pHEMA (M-pHEMA) nanogel and NiFe2O4/pHEMA (NF-pHEMA) nanogel structures were produced by the photochemical method. The characterization of these materials was performed by FTIR, SEM, AFM analysis. Then, the lipase enzyme was immobilized on magnetic nanogels by adsorption and after that cross-linking method under optimum conditions. For the characterization of lipase immobilized magnetic nanogels; optimum temperature, thermal stability, optimum pH, pH stability, reusability and kinetic parameters were investigated and nature and immobilized lipase were compared. It was observed that there was a significant improvement in the thermal and pH stability of the immobilized enzyme compared to the free enzyme. Lipase-immobilized M-pHEMA lost 50% of its activity after 15 uses and after 16 uses of lipase-immobilized NF-pHEMA. The results show that immobilization to the synthesized magnetic nanogels provides an improvement in the properties of the lipase enzyme. It is thought that the synthesized magnetic nanogels can be an alternative for different applications, especially drug delivery systems.