Gold nanoparticles are used in life science applications extensively because of their biocompatibility and how easily they can be paired with organic molecules.
Control over the size and structure of nanoparticles is key to supplying reliable and reproducible results. Gold nanoparticles of various sizes in solution are commerically available. However, such nanoparticles are quite often contaminated with hydrocarbons due to the chemical synthesis and clump together in solution.
The NL50 provides an unconventional route to generate monodisperse and ultra-pure gold nanoparticles which contain no contaminants. The NL50 produces nanoparticles from the solid source material with 99.999% purity.
The nanoparticles are produced in a vacuum utilizing a process called magnetron sputtering, where atoms are knocked from the source material by energized gas ions. These atoms form nanoparticles by clumping together.
The size of the nanoparticles can be manipulated by adjusting the parameters of the process inside the NL50, including gas flow and magnetron power.
The NL50 can generate nanoparticles from any conductive material, including gold, silver, platinum, copper, titanium and nickel. The video explainer demonstrates how the NL50 works.
Lifting the lid on the NL50
Video Credit: Nikalyte Ltd
The ultra-pure nanoparticles are pulled out of the NL50’s nanoparticle creation zone and moved into the sample chamber, where they land onto the substrate.
The NL50 can deposit nanoparticles onto any solid substrate, including plastic, glass and metal, that has been loaded through the transparent sample door by the operator.
Gold nanoparticles were placed on holey carbon grids (supplied by Agar Scientific) for TEM analysis. The TEM analysis was performed by Max Astle and Rhys Lodge at the Nottingham Nanoscale and Microscale Research Centre (nmRC) utilizing a JEOL 2100F FEG-TEM microscope running at 200 keV.
Figure 1 displays TEM images of the gold nanoparticles, verifying that the nanoparticles are discrete, crystalline and form the common icosahedral structure. Figure 2 demonstrates that the nanoparticles have size distribution tightly centered around 22nm. In the high-resolution image, exhibited in figure 3, the distinct gold atoms are clearly distinguishable.
Figure 1. Gold Nanoparticles prepared in vacuum in the NL50. Image Credit: Nikalyte Ltd
Figure 2. Size distribution of gold nanoparticles from Figure 1. Image Credit: Nikalyte Ltd
Figure 3. High resolution image of gold nanoparticle showing icosahedral structure. Image Credit: Nikalyte Ltd
The NL50 can also produce smaller nanoparticles by adjusting the process conditions. Figure 4 displays TEM images of smaller nanoparticles with sizes of 4.5 and 6.5nm. While the smaller nanoparticles are also crystalline, the shape is more spherical than the larger nanoparticles.
Figure 4. Small gold nanoparticles generated in the NL50 with diameters of 4.5nm (left) and 6.5nm (right). Image Credit: Nikalyte Ltd
This information has been sourced, reviewed and adapted from materials provided by Nikalyte Ltd.
For more information on this source, please visit Nikalyte Ltd.