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Updated: Feb 11, 2026
08:23
Design and Development of Aptamer–Gold Nanoparticle Based Colorimetric Assays for In-the-field Applications
Published on: June 23, 2016
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Gold nanoparticle-based colorimetric method for the detection of prostate-specific antigen
Ning Xia1, Dehua Deng1,2, Yiru Wang1
1Henan Province of Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan, People's Republic of China.
International Journal of Nanomedicine
|May 8, 2018
Summary
This study presents a novel colorimetric assay for detecting prostate-specific antigen (PSA) using gold nanoparticles. The method offers sensitive and specific PSA detection, aiding in prostate cancer diagnosis and monitoring.
Area of Science:
- Biomedical Engineering
- Nanotechnology
- Analytical Chemistry
Background:
- Prostate-specific antigen (PSA) is a crucial biomarker for prostate cancer diagnosis, screening, and post-treatment monitoring.
- Accurate and sensitive detection of PSA is essential for effective patient management.
Purpose of the Study:
- To develop a novel colorimetric method for the clinical detection of PSA.
- To utilize gold nanoparticles (AuNPs) as reporters for sensitive PSA quantification.
Main Methods:
- A colorimetric assay based on ascorbic acid (AA)-induced gold nanoparticle formation.
- Copper(II) ions (Cu2+) catalyze AA oxidation, inhibiting AuNP formation.
- PSA-specific peptide-modified magnetic microbeads capture Cu2+, allowing AuNP formation; PSA cleavage releases Cu2+, inhibiting AuNP formation.
Main Results:
- The assay demonstrated a linear detection range of 0–0.8 ng/mL for PSA.
- A low detection limit of 0.02 ng/mL was achieved.
- Separation of cleavage and measurement steps minimized matrix interference in biological samples.
Conclusions:
- The high extinction coefficient of AuNPs enables sensitive colorimetric analysis of PSA in serum.
- This approach provides a foundation for designing other protease biosensors by employing specific peptide substrates.
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