About Gold Nanoparticles
- Gold nanoparticles (AuNPs) are small gold particles with a diameter of 1 to 100 nm.
- Once dispersed in water, AuNPs are also known as colloidal gold.
- These are also called as ‘gold bhasma,’
- Properties
- Spherical AuNPs possess useful attributes such as size- and shape-related optoelectronic properties, large surface-to-volume ratio, excellent biocompatibility, and low toxicity.
- Important physical properties of AuNPs include surface plasmon resonance (SPR) and the ability to quench fluorescence.
- Spherical AuNPs exhibit a range of colors (e.g., brown, orange, red and purple) in aqueous solution as the core size increases from 1 to 100 nm.
- These are not – toxic, not phototoxic, not genotoxic, non-irritant and non-sensitizing
- Applications
- Electronics: Gold nanoparticles are designed for use as conductors from printable inks to electronic chips. Nanoscale gold nanoparticles are being used to connect resistors, conductors, and other elements of an electronic chip.
- Photodynamic Therapy: Near-IR absorbing gold nanoparticles produce heat when excited by light at wavelengths from 700 to 800 nm. This enables these nanoparticles to eradicate targeted tumors.
- Therapeutic Agent Delivery: Therapeutic agents can also be coated onto the surface of gold nanoparticles. The large surface area-to-volume ratio of gold nanoparticles enables their surface to be coated with hundreds of molecules
- Sensors – These are used in a variety of sensors. For example, a colorimetric sensor based on gold nanoparticles can identify if foods are suitable for consumption.
- Diagnostics: These are also used to detect biomarkers in the diagnosis of heart diseases, cancers, and infectious agents.
Q1) What is nanotechnology?
Nanotechnology is the manipulation of matter on a near-atomic scale to produce new structures, materials and devices. The technology promises scientific advancement in many sectors such as medicine, consumer products, energy, materials, and manufacturing.
Last updated on November, 2025
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