A biochip based on shell-isolated Au@MnO₂ nanoparticle array-enhanced fluorescence effect for simple and sensitive...

Area of Science:

• Biomarker Discovery
• Nanotechnology
• Analytical Chemistry

Background:

• Exosomes are crucial biomarkers for liquid biopsy due to their molecular cargo.
• Current exosome detection methods often rely on complex nucleic acid amplification.
• A need exists for simpler, more sensitive exosome detection techniques.

Purpose of the Study:

• To develop a simple and highly sensitive method for exosome assay using metal-enhanced fluorescence (MEF).
• To utilize a shell-isolated Au@MnO2 nanoparticle array for enhanced exosome detection.
• To establish a novel strategy for exosome-based liquid biopsy.

Main Methods:

• Designed a metal-enhanced fluorescence (MEF) biochip utilizing a shell-isolated Au@MnO2 nanoparticle array.
• Employed a chain displacement reaction for exosome signal conversion to DNA signals.
• Achieved dual signal amplification through signal conversion and MEF amplification.

Main Results:

• The MEF biochip demonstrated high sensitivity for exosome detection with a limit of 4.5 × 10^3 particles/μL.
• Sensitivity was enhanced approximately thirtyfold compared to methods without MEF.
• The method successfully distinguished breast cancer patients from healthy individuals.

Conclusions:

• The developed MEF biochip offers a simple, sensitive, and stable platform for exosome detection.
• This strategy represents the first application of MEF for exosome assay.
• The technology shows significant potential for noninvasive liquid biopsy, particularly in cancer diagnostics.