Cost-effective and sensitive colorimetric immunosensing using an iron oxide-to-Prussian blue nanoparticle conversion...

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Analytical Chemistry

Background:

• Increasing demand for sensitive, cost-effective, and user-friendly colorimetric bioassays for clinical diagnostics and field detection.
• Need for innovative approaches in nanoparticle-based biosensing for enhanced sensitivity and practicality.

Purpose of the Study:

• To develop a novel iron oxide-to-Prussian blue nanoparticle conversion strategy for sensitive colorimetric immunosensing.
• To apply this strategy for the detection of cancer biomarkers, specifically prostate-specific antigen (PSA).

Main Methods:

• Development of a sandwich-type immunosensing system utilizing antibody-conjugated iron oxide nanoparticles.
• Conversion of captured iron oxide nanoparticles into Prussian blue nanoparticles for colorimetric signal generation.
• Detection of prostate-specific antigen (PSA) in human serum samples.

Main Results:

• Successful transformation of iron oxide nanoparticles into Prussian blue nanoparticles, yielding a highly visible blue color.
• Achieved sensitive detection of PSA down to 1.0 ng mL(-1) by the naked eye without complex signal amplification.
• Demonstrated good reliability in detecting PSA in real human serum samples.

Conclusions:

• The iron oxide-to-Prussian blue nanoparticle conversion strategy offers a novel, sensitive, and cost-effective approach for colorimetric immunosensing.
• This method shows significant promise for developing user-friendly bioassays suitable for various bioanalytical applications, particularly in resource-limited settings.
• The developed strategy represents a significant advancement in nanoparticle-based colorimetric bioassays for biomarker detection.