What characteristics make gold an ideal material for such wide-ranging applications? The nobility of gold and its resistance to surface oxidation (which would hinder the operation of nano-scale technologies and devices based on other metals) is one important material characteristic. The optical properties of gold at the nanoscale are also exciting, (gold nanoparticles have a colour varying from red to purple depending on particle size, a property that can be successfully exploited in a range of applications).

 

Use of gold nanoparticles improves the drug delivery efficiency of this anticancer drug
(Credit – Eugen Zubarev/Rice University)

 

Additionally, gold nanoparticles are now known to be catalytically active for a range of commercially important reactions and they also have a surface chemistry particularly suited to the attachment of sulphur-containing molecules, such as thiols, which permits the ‘bottom-up’ assembly of interesting and useful structures.

 

Based on these unique properties, exciting new nanotechnology applications using gold are being developed. These include:

• Low resistance printable gold nanoparticulate inks for flexible electronics • Gold nanowires for interconnections in future electronic devices • Nanoparticulate gold colloid for rapid tests and biomedical assays • Gold nanoparticles used for targeted delivery of anticancer drugs and destruction of cancer cells • Improved decorative coatings using thiol stabilised gold nanoparticles • Gold nanoparticle containing paints and textiles exhibiting novel aesthetic effects • Nanoparticulate gold catalysts for pollution control and chemical synthesis • Fuel cell electrocatalysts based on carbon supported nanoparticulate gold		Use of gold inks to ink-jet ultra high resolution images (Credit – IBM Zurich Research Laboratory)
Use of gold nanoparticles to colour merino wool (Credit – University of Victoria, New Zealand)		For the very latest information on gold-related nanotechnology read the latest issue of NanoTech Gold News   Visit the site of this French research network focused on multi-disciplinary investigations into gold nanotechnology
Dr Richard Holliday, Head of Industrial Applications at World Gold Council gives an interview to Small Times about gold nanomaterials at the 'NanoTech 2008' event http://www.smalltimes.com/video/index.cfm