Enhanced glucose detection using dendrimer encapsulated gold nanoparticles benefiting from their zwitterionic surface

Area of Science:

• Nanotechnology
• Biochemistry
• Analytical Chemistry

Background:

• Ultrasmall gold nanoparticles are increasingly utilized as enzyme mimics.
• Developing sensitive and selective detection methods for glucose is crucial for medical diagnostics.

Purpose of the Study:

• To develop zwitterionic dendrimer encapsulated gold nanoparticles (Au-G5MC NPs) for sensitive and simple colorimetric glucose detection.
• To investigate the peroxidase-like properties and kinetics of Au-G5MC NPs.

Main Methods:

• Synthesis of zwitterionic dendrimer encapsulated gold nanoparticles (Au-G5MC NPs).
• Characterization of Au-G5MC NPs' peroxidase-like activity using 3,3',5,5'-tetramethylbenzidine (TMB) and H2O2.
• Michaelis-Menten kinetic analysis.
• Colorimetric detection of glucose concentration.

Main Results:

• Au-G5MC NPs demonstrated significant peroxidase-like activity, catalyzing TMB oxidation.
• The K m value for TMB was lower than that of horseradish peroxidase (HRP), indicating higher efficiency.
• A linear detection range for glucose from 14 μM to 166 μM was established with a detection limit of 3.8 μM.
• The zwitterionic layer prevented protein interference, ensuring high selectivity.

Conclusions:

• Au-G5MC NPs serve as effective enzyme mimics with excellent peroxidase-like properties.
• The developed method offers a sensitive, selective, and simple approach for colorimetric glucose detection.
• This catalytic system holds significant potential for applications in medical diagnostics and biochemical analysis.