Enhancement of Catalytic Stability and Kinetic Evaluation of Acetylcholinesterase Immobilized on Functionalized Fe3O4 Magnetic Nanoparticles


Başaran S., IŞIK M.

ChemistrySelect, cilt.10, sa.30, 2025 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 10 Sayı: 30
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1002/slct.202502600
  • Dergi Adı: ChemistrySelect
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier
  • Anahtar Kelimeler: Acetylcholinesterase immobilization, Enzyme kinetic, Enzyme stability, Functionalization, Magnetic nanoparticles
  • Bilecik Şeyh Edebali Üniversitesi Adresli: Evet

Özet

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.