Glutamate oxidase-integrated biomimetic Fe3O4 hybrids as cascade nanozymes for glutamate detection

• Published in: Particuology 2024-05, Vol.88, p.192-200
• Main Authors: Li, Peikun, Wang, Yanchao, Luo, Xiuyan, Geng, Zixin, Jia, Jiahui, Wang, Ruirui, Cui, Jiandong, Bian, Hongjie, Jia, Shiru
• Format: Article
• Language: English
• Subjects: Chemo-enzymes; Fe3O4 nanozyme; GLOD; Glutamate detection
• ISSN: 1674-2001; 2210-4291
• DOI: 10.1016/j.partic.2023.09.006

Herein, a new nanozyme/natural enzyme hybrid biosensor was established for ultrasensitive l-glutamic acid (L-Glu) detection. The Fe3O4 nanoparticles with peroxidase-like activity and stability was used as a nanozyme and carrier for immobilizing l-Glutamate oxidase (GLOD) through Schiffff base reaction to construct a chem-enzyme cascade detector. The resultant Fe3O4-GOLD exhibited a wide linear range (10−500 μM) and a low detection limit of 6.03 μM for L-Glu detection. Furthermore, the Fe3O4-GOLD exhibited excellent pH stability, thermal stability, reusability and storage stability. After repeated nine cycles, Fe3O4-GOLD still retained 70% of its initial activity. Meanwhile, Fe3O4-GOLD maintained 50% of its initial activity after storage for 20 days, while free GLOD only retained 20% of its initial activity. This strategy of integrating biomimetic Fe3O4 and natural enzymes for cascade catalysis makes it possible to design an efficient and stable chemo-enzyme composite catalysts, which are promising for applications in biosensing and biomimetic catalysis. [Display omitted] •A new Glutamate oxidase-integrated biomimetic Fe3O4 hybrids was prepared.•Hybrids exhibited a good linear range of 10–500 μM and a LOD of 6.03 μM for glutamate.•Glutamate biosensor is a promising candidate for applications in biosensing for detection of glutamate.