What Are Nanoclusters?

Nanoclusters are gold compounds with a core of metal atoms and organic groups covalently bound to the surface gold atoms. Due to their small size, these nanoclusters exhibit intrinsic near-infrared (NIR) fluorescence.

What is cluster in nanotechnology?

Clusters are small aggregates of atoms and molecules. Small means really tiny pieces of matter—they are composed of a few to thousands of units and have a diameter of nanometers. Nanoclusters have at least one dimension between 1 and 10 nm and a narrow size distribution. Nanoclusters are composed of up to 100 atoms, but bigger ones containing 1000 or more are called nanoparticles.

What are nanoclusters used for?

Nanoclusters have potential uses in chemical reactors, telecommunications, microelectronics, optical data storage, catalysts magnetic storage, spintronic devices, electroluminescent displays, sensors, biological markers, switches, transducers and many other fields. The florescence silver nanoclusters have been extensively used as biological markers for photodynamic therapy

What are metal nanoclusters?

Metal nanoclusters (NCs) are composed of a small number of atoms, up to dozens. These nanoclusters can consist of a single element or multiple elements, usually smaller than 2 nm. Compared with their larger counterparts, this nanocluster exhibits attractive electronic, optical and chemical properties.

These particles have quasi-continuous energy levels and display intense colors due to surface plasmon resonance. If their dimension is further reduced to the size approaching the Fermi wavelength of electrons, the band structure becomes discrete energy levels. The ultrasmall metal nanoparticles display molecule-like properties and no longer exhibit plasmonic behavior. Metal NCs, such as AuNCs, AgNCs, CuNCs, and PtNCs, exhibit a marked photoluminescence property due to quantum confinement. The most studied among these metal NCs are Au NCs, AgNCs, and CuNCs.

What are gold nanoclusters?

Nanocluster are collective groups composed of a specific number of atoms or molecules held together through a certain interaction mechanism. Gold nanoclusters  attract increasing attention due to their potential applications in sensing, catalysis, optoelectronics, and biomedicine.

How are gold nanoclusters made?

In one example, green-emitting gold nanoclusters could be prepared by adding mercaptoundecanoic acid (MUA) into small AuNP solutions prepared by the reduction of HAuCl4 with tetrakis(hydroxymethyl)phosphonium chloride (THPC).

About the author

As a provider of a comprehensive list of coated, functional and conjugated gold nanoparticles, Creative Diagnostics now offers gold nanoclusters terminated by carboxylic acid groups or amine groups that can be used to immobilize covalently biomolecules. Products such as SpecNano™ Amine Gold Nanoclusters, 1.5 nm(NI-NA01), SpecNano™ Carboxyl Gold Nanoclusters, 0.8-1.0 nm(NI-NC01), and SpecNano™ Carboxyl Gold Nanoclusters, 2.0 nm(NI-NC03) are available at Creative Diagnostics now.

References

1. Jiang, K., & Pinchuk, A. O. (2015). Noble metal nanomaterials: synthetic routes, fundamental properties, and promising applications. Solid State Physics, 66, 131-211.
2. Peng, G., Umair, M., Hussain, I., & Javed, I. (2020). Nanosilver at the interface of biomedical applications, toxicology, and synthetic strategies. Metal Nanoparticles for Drug Delivery and Diagnostic Applications, 119-139.
3. Freitas de Freitas, L., Varca, G. H. C., dos Santos Batista, J. G., & Benévolo Lugão, A. (2018). An overview of the synthesis of gold nanoparticles using radiation technologies. Nanomaterials, 8(11), 939.