International Gold Nanoparticles Definition
International gold nanoparticles (AuNPs) are sub-micrometer sized particles of gold that are typically synthesized through chemical reduction of gold salts in the presence of a stabilizing agent. They possess unique optical, electronic, and physicochemical properties that stem from their size, shape, and surface chemistry.
The International Organization for Standardization (ISO) defines AuNPs as “particles of gold with a diameter less than 100 nm.” This broad definition encompasses a wide range of AuNPs with distinct properties and applications.
Key Characteristics of AuNPs:
* Size and Shape: AuNPs can vary in size from a few nanometers to hundreds of nanometers. Their shape can range from spherical to rod-like, cubic, or triangular, each with specific properties.
* Surface Chemistry: The surface of AuNPs can be modified with various ligands, such as sulfur-containing molecules, polymers, or biomolecules, to control their stability, reactivity, and biocompatibility.
* Optical Properties: AuNPs exhibit a characteristic surface plasmon resonance (SPR) band due to the collective oscillation of electrons at their surfaces. The SPR band position and intensity are highly sensitive to the particle size, shape, and dielectric environment.
* Electronic Properties: AuNPs have unique electronic properties, including high conductivity and tunable bandgap, which enable their use in electronic devices and sensors.
Applications of AuNPs:
AuNPs have a wide range of applications in various fields, including:
* Medicine: Drug delivery, tumor imaging, and photothermal therapy
* Electronics: Transistors, sensors, and solar cells
* Catalysis: Chemical reactions, fuel cells, and environmental remediation
* Optics: Plasmonics, metamaterials, and nonlinear optics
* Cosmetics: Sunscreen and skin care products
Regulation and Standardization:
The use of AuNPs in commercial products and medical applications requires stringent regulation and standardization to ensure safety and efficacy. Various national and international organizations, including ISO, the US Food and Drug Administration (FDA), and the European Chemicals Agency (ECHA), have established guidelines for the characterization, testing, and labeling of AuNPs.
In conclusion, international gold nanoparticles are a versatile class of materials with a wide range of properties and applications. Their unique characteristics and the ability to control their size, shape, and surface chemistry make them valuable for advancements in various scientific and technological fields.
原创文章，作者：Kevin，如若转载，请注明出处：https://fangeou.com/2983.html
