A magnetic nanoscale Fe3O4/Pβ-CD composite as an efficient peroxidase mimetic for glucose detection

• Fe3O4/Pβ-CD was fabricated by a simple and general one-pot solvothermal method.
• Sensitive and selective detection of glucose in human serum was achieved.
• Fe3O4/Pβ-CD composite showed good reusability for H2O2 detection.
• Possible catalytic mechanism of Fe3O4/Pβ-CD composite was proposed.

Magnetic polymer particles with different surface functionalizations were prepared by a simple one-pot solvothermal method and characterized as peroxidase mimetics. The fluorescence enhancement obtained by attaching a β-cyclodextrin polymer (Pβ-CD) to the surfaces of Fe3O4 magnetic microspheres (Fe3O4 MMs) to generate a Fe3O4/Pβ-CD composite allowed the rapid, sensitive and selective analysis of glucose. The catalytic activity of the Fe3O4/Pβ-CD composite was evaluated with regard to the effects of catalyst particle size and species, pH value, level of catalyst, benzoic acid concentration and reaction time. Detection limits of 0.015 μM for H2O2 and 0.03 μM for glucose were determined when measuring at the 10-min mark. The presence of other saccharides, ion species, amino acids and proteins, had little effect on the results, and this technique was found to allow the analysis of glucose in human serum with high accuracy. The reusability of the Fe3O4/Pβ-CD composite was also investigated after 10 successive runs. A possible mechanism is proposed in which Fe3O4 plays a significant role in inducing fluorescence and Pβ-CD enhances the fluorescence signal, acting as both a stabilizer and a phase transfer agent.

Magnetic polymer particles with different surface functionalizations were prepared by a simple one-pot solvothermal method and characterized as peroxidase mimetics. Due to the fluorescence enhancement of β-CD polymer (Pβ-CD) on the surface of the Fe3O4 magnetic microsphere (Fe3O4 MMs), the Fe3O4/Pβ-CD composite has been composed for the rapid, sensitive, and selective fluorescence detection of glucose. The catalytic activity of the Fe3O4/Pβ-CD composite was evaluated in view of catalyst particle size and species, pH value, catalyst addition, benzoic acid concentration and time. The detection limits of 0.015 μM for H2O2 and 0.03 μM for glucose were obtained for 10 min. Other saccharides, such as fructose, galactose, sucrose, and maltose, have little influence on the detection of glucose and the glucose in human serum was detected with high accuracy. The reusability of the Fe3O4/Pβ-CD composite was also investigated after 10 successive runs. Possible mechanism was proposed that the Fe3O4 played a significant role in inducing fluorescence and the Pβ-CD enhanced the fluorescence signals, acting as stabilizer and phase transfer agent.Figure optionsDownload as PowerPoint slide