Possessing unique optical properties, gold nanoparticles have been widely used in biomedical and diagnostics applications for a number of years. We profile applications and leading producers in this market.
Gold nanoparticles (Au-NPs) are widely used due to unique optical properties. These properties are conferred by the interaction of light with electrons on the gold nanoparticle surface. At a specific wavelength of light, collective oscillation of electrons on the gold nanoparticle surface cause surface plasmon resonance, resulting in strong extinction of light. The particular wavelength, or frequency, of light where this occurs is strongly dependant on the gold nanoparticle size, shape, surface and agglomeration state.
Au-NPs have been commercialized in biomedicine for use as immunohistochemistry bio markers. They are also used in applications such as DNA delivery because of their low cytotoxicity and ease of functionalization with various ligands of biological significance. Other medical applications include cancer therapy, photothermal agents, contrast agents and radiosensitisers. Over the past few years, Au-NPs have been widely sued in the lateral flow point of care test market. 40nm gold colloid is mainly utilized due to its size, suitability and its rich cherry red colour. The 40nm particles provide an ideal platform for attaching the majority of human related antibodies and as on a white background the red line produced can easily be viewed and quantified.
Markets
Main current markets for Au-NPs are biomedicine and electronics/photonics, mainly as contrast agents and in drug delivery. Current prices range from $250-$750/100ml. Main producers are Cyto-Diagnostics, Sigma-Aldrich, Strem Chemical, Nanocs and BBI Solutions.
High volume applications
• Medical (in-vitro-diagnostics).
• Conductors in electronics.
• Light microscopy contrast agents.
• High Magnification TEM contrast agents.
• Drug delivery.
• Bioimaging.
Low volume applications
• Gas sensors.
• Coatings.
• Catalysis.
• Chemical sensors.
• DNA detection.
• Electronic inks.
Novel applications
• Environmental detection and purification.
• Data storage.
