Ultrasensitive electrochemical biosensor based on the oligonucleotide self-assembled monolayer-mediated immunosensing...

Area of Science:

• Biosensors
• Electrochemistry
• Biomarker Detection

Background:

• Accurate protein quantitation is crucial for disease diagnostics.
• Existing methods often lack sensitivity or specificity.
• Developing ultrasensitive and selective biosensors is a key research area.

Purpose of the Study:

• To develop an electrochemical immunosensing platform for highly sensitive and selective protein detection.
• To utilize an oligonucleotide self-assembled monolayer (OSAM) for improved biosensing performance.
• To demonstrate the platform's capability using human immunoglobulin G (HIgG) as a model.

Main Methods:

• Fabrication of an electrochemical biosensor using a gold electrode modified with thiolated single-stranded DNA (OSAM).
• Integration of a "signal-on" mechanism and enzymatic signal amplification.
• Electrochemical detection of HIgG using cyclic voltammetry or impedance spectroscopy.

Main Results:

• The OSAM interface facilitated electron transfer and prevented non-specific protein adsorption.
• The immunosensor achieved ultrasensitive detection of HIgG down to 0.5 ng/mL.
• High specificity was demonstrated, minimizing cross-reactivity.

Conclusions:

• The developed OSAM-mediated electrochemical immunosensor provides a robust platform for protein detection.
• The biosensor exhibits high sensitivity and selectivity, suitable for biomarker detection.
• Oligonucleotide probes show significant potential for biological research and biomedical diagnostics.