SYNTHESIS OF NANOSTRUCTURED Fe3O4@C CORE-SHELL WITH PEROXIDASE LIKE ACTIVITY AND ITS APPLICATION FOR FABIRCATION OF COLORIMETRIC CHOLESTEROL BIOSENSOR

Abstract

In this study, we presented the results of the research on the fabrication of Fe3O4 nanoparticles coated with
carbon layer (nanostructured Fe3O4@C material) via a simple route. The peroxidase-like catalytic activity
of Fe3O4@C was evaluated using Michaelis – Menten and Lineweaver-Burk model. Results indicated that
Fe3O4@C had strong peroxidase-nanozyme activity than that of horseradish peroxidase (HRP) –a natural
enzymee. Therefore, the synthesized of Fe3O4@C nanozyme was applied to replace of HRP for combining
with cholesterol oxidase enzymee (ChOx) to fabricate of a colorimetric biosensor for cholesterol detection.
Obtained results showed that the developed biosensor had high selectivity, and it coud detect cholesterol in
a linear range of 0.05 to 1.5 mM and with the limit of detection (LOD) was 0.01 mM. The developed
biosensor could also detecte cholesterol in real samples (human serum sample), which implied that the
cholesterol sensor performed well in complex environments, demonstrating its high application potential to
replace of HRP in developing of biosensor for cholesterol concentrations in real samples.