Research Information System
ChemistrySelect, vol.10, no.30, 2025 (SCI-Expanded, Scopus)
In this study, Fe3O4 magnetic nanoparticles (MNPs) were synthesized, and the acetylcholinesterase (AChE) enzyme was immobilized on the functionalized MNPs using the cross-linker glutaraldehyde. The immobilized enzyme (Fe3O4@SiO2-NH2/GA/AChE) was characterized by scanning electron microscopy-energy scattering spectroscopy (SEM-EDX) and FTIR. Activity for optimum pH was determined in the range of pH 5–11 for free and immobilized enzyme, and the highest activity was observed at pH 8 for free AChE and pH 10 for immobilized AChE. When the kinetic parameters were examined, the Km and Vmax values of immobilized AChE were 0.446 mM and 0.659 EU mL−1, respectively, while those of free AChE were 0.163 mM and 0.965 EU mL−1, respectively. The binding affinity of the tacrine inhibitor to the enzyme was lower for the immobilized enzyme than for the free enzyme. Storage stability tests showed that immobilized AChE stored at 4 °C for 60 days retained 95.2% of its activity, while the free enzyme lost 50.4 % of its activity. Furthermore, reuse tests performed for 20 replicates showed that immobilized AChE retained more than 95% of its initial activity. Therefore, the high stability and reusability of the enzyme as a result of the immobilization process may contribute to future studies in terms of biotechnological applications.