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Design and Development of Aptamer–Gold Nanoparticle Based Colorimetric Assays for In-the-field Applications
Published on: June 23, 2016
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Colorimetric Immunosensor by Aggregation of Photochemically Functionalized Gold Nanoparticles
Marzia Iarossi1, Chiara Schiattarella1,2, Ilaria Rea2
1Department of Physics "E. Pancini", Università di Napoli "Federico II", Via Cintia, 26 Ed. 6, 80126 Napoli, Italy.
ACS Omega
|July 20, 2018
Summary
This study presents a simple, low-cost colorimetric immunosensor using gold nanoparticles for detecting human immunoglobulin G (IgG). The sensor enables rapid, visual detection of IgG in samples, useful for medical diagnostics.
Area of Science:
- Nanotechnology
- Biomedical Engineering
- Analytical Chemistry
Background:
- Gold nanoparticles exhibit Local Surface Plasmon Resonance (LSPR) properties.
- Colorimetric detection offers a simple and rapid analytical method.
- Human Immunoglobulin G (IgG) is a key biomarker in various medical conditions.
Purpose of the Study:
- To develop a novel colorimetric immunosensor for Human IgG detection.
- To utilize gold nanoparticle aggregation for signal generation.
- To provide a cost-effective and efficient diagnostic tool.
Main Methods:
- Functionalization of gold nanoparticles with antibodies for IgG recognition.
- Induction of nanoparticle aggregation upon analyte binding.
- Visual detection of color change in colloidal solution.
- Characterization of dose-response curve and theoretical modeling.
Main Results:
- Demonstrated successful detection of Human IgG using the developed immunosensor.
- Achieved visual detection of IgG at concentrations in the hundreds of nanograms per milliliter.
- Observed rapid detection within minutes.
- Validated the sensor's performance against a theoretical model.
Conclusions:
- The developed gold nanoparticle-based colorimetric immunosensor is a simple, low-cost, and effective tool for Human IgG detection.
- The sensor allows for rapid, visual identification of the analyte.
- Potential applications include point-of-care diagnostics, particularly in urine testing for medical purposes.
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