Gold Nanoparticles Strange properties and applications
Expedeon
Published on Jul 22, 2013
Gold nanoparticles exhibit extraordinary properties quite unlike those of the bulk metal. These properties can be exploited in a variety of assay applications, including lateral flow tests, microscopy, flow cytometry and FRET assays. There are also a number of therapeutic applications, especially in the field of cancer. This free and exciting webinar focuses on the following points:
1. Introduction to Gold
2. Unique properties of nanoparticles
3. Why does “40nm gold” never look the same from different suppliers?
4. Methods of attaching proteins and analytes to gold
5. Uses of nanoparticles in diagnostics
6. Uses of nanoparticles in therapeutics
This video was produced by Innova Biosciences which is now fully integrated with their company, Expedeon Ltd.
To find out more visit our website at www.expedeon.com
Gold nanoparticles (AuNPs) are particles of gold with dimensions ranging from 1 to 100 nanometers. At this nanoscale, gold exhibits unique physical, chemical, and optical properties that differ significantly from its bulk form, making AuNPs a focal point in various scientific and technological fields.
Unique Properties of Gold Nanoparticles
- Optical Characteristics: One of the most remarkable features of AuNPs is their optical behavior, particularly the surface plasmon resonance (SPR). SPR occurs when conduction electrons on the nanoparticle’s surface oscillate in resonance with incident light, leading to strong absorption and scattering. This phenomenon imparts vibrant colors to AuNPs, with variations in size and shape resulting in different hues. For instance, spherical AuNPs typically appear red, while larger or rod-shaped particles can appear blue or purple.
- Surface Chemistry: AuNPs possess a high surface-area-to-volume ratio, providing ample surface sites for functionalization. This property allows for the attachment of various ligands, including drugs, antibodies, and polymers, facilitating targeted interactions in biomedical applications.
- Electronic Properties: At the nanoscale, gold exhibits size-dependent electronic properties. AuNPs can act as conductors or semiconductors, making them valuable in electronic and sensing applications.
Applications of Gold Nanoparticles
- Medical Diagnostics and Therapeutics: The biocompatibility and functionalization versatility of AuNPs have led to their use in various medical applications. In diagnostics, AuNPs are employed in assays and imaging techniques due to their optical properties. Therapeutically, they are explored in drug delivery systems and photothermal therapies, where AuNPs convert light into heat to target and destroy cancer cells.
- Electronics: In the realm of electronics, AuNPs serve as conductive materials in printable inks and are integral components in the fabrication of nanoscale circuits and devices. Their ability to facilitate electron transfer at the nanoscale is crucial for the development of smaller and more efficient electronic components.
- Catalysis: AuNPs exhibit catalytic properties, particularly in oxidation reactions. Their high surface area and active sites make them effective catalysts in chemical processes, including environmental applications like pollutant degradation.
- Sensing: The sensitivity of AuNPs to changes in their environment, especially alterations in the local refractive index, underpins their use in sensor technologies. They are utilized in biosensors for detecting biomolecules, pathogens, and environmental toxins, offering high sensitivity and specificity.
Challenges and Considerations
Despite their advantageous properties, the application of AuNPs presents challenges. Ensuring the stability of AuNPs in various environments is essential to prevent aggregation, which can alter their properties. Additionally, understanding the interactions between AuNPs and biological systems is crucial to assess potential cytotoxicity and ensure biocompatibility. Surface functionalization strategies are often employed to enhance stability and compatibility.
Conclusion
Gold nanoparticles exemplify the transformative potential of nanotechnology, where materials exhibit novel properties distinct from their bulk counterparts. The unique characteristics of AuNPs have paved the way for innovations across multiple disciplines, from medicine to electronics. Ongoing research continues to uncover new applications and methodologies to harness the full potential of these remarkable nanomaterials.
