In this blog post, we will look at the innovation brought about by silver nanotechnology and the potential risks that come with it, and whether the future technology will be a blessing or a challenge.
Recently, the word “nano” has been easily seen everywhere. Nanotechnology has been applied to various fields, and these technologies have penetrated deeply into our daily lives. Nanotechnology is used in all areas, from smartphones to cosmetics and medical devices. But what does this nanotechnology mean and how is it changing our lives?
The word “nano” is said to have originated from the ancient Greek word “nanos,” which means “dwarf.” 1 nm, or nanometer, is one billionth of a unit, which is so small that it cannot be seen with the naked eye. Nanotechnology refers to the technology of synthesizing, assembling, and controlling materials of such a very small size, and it is also a scientific methodology for identifying and measuring the properties of such materials. It is a pillar of advanced science and an important foundation for the development of modern technology. As such, nanotechnology has enabled a number of innovative products that were not possible in the past. The possibilities of nanotechnology are endless, and it is being experimented with and applied in various fields.
In particular, it is technically very difficult to process metals such as gold and silver into nanoscale. The atoms of these metals have a very strong binding force with each other, so when processed into nanoscale, they tend to clump together. Gold and silver, which we normally know, are known to have very good ductility (flexibility) and malleability (the property of stretching well), but when reduced to nanoscale, their properties change significantly. For example, in the case of silver, it has been observed that when a thin silver foil is made thinner than 100 nanometers (nm), the silver atoms tend to clump together, causing the silver foil to fold rather than spread out. This is one of the reasons why silver is not widely used despite its superior electrical and thermal conductivity compared to copper, which makes it a potential candidate for use in electronic components.
However, these properties of silver are opening up new possibilities through various nanotechnologies. For example, when silver becomes nanoparticles, its properties change in a completely different direction. Silver nanoparticles have strong sterilizing power, and washing machines and water purifiers using them have been developed. In particular, washing machines using silver nanoparticles are attracting attention because they can effectively remove germs. While traditional silver is resistant to oxidation and does not kill germs, silver nanoparticles react well with surrounding substances due to their size and have excellent ability to destroy germs.
The representative silver nanoparticles washing machines in Korea are divided into products from companies S, L, and D. Company S uses a method that generates silver ions using electricity inside the washing machine and removes germs through this. Company L coats the inside of the washing machine with silver nanoparticles to achieve an antibacterial effect, while Company D achieves a similar effect by mixing silver powder into the washing tub itself.
There are three scientific explanations for the antibacterial action of silver nanoparticles. First, silver nanoparticles damage the cell membrane of bacteria, making it difficult for them to survive. Second, silver acts as a catalyst to accelerate the aging of bacteria. Third, silver nanoparticles are similar in size to the food of bacteria, so when bacteria ingest them, they cause metabolic disorders and eventually death.
However, despite this innovative technology, in 2006, the U.S. Environmental Protection Agency (EPA) banned the export of silver nanoparticles washing machines from Company S in Korea. This is because concerns have been raised that silver nanoparticles may be harmful to the human body. Silver nanoparticles are classified as disinfectants, and there has not been sufficient verification of the side effects that may occur if they come into contact with the human body or spread to the environment. This means that consumers should be more careful when using silver nanowashers.
Unlike the general properties of silver, silver nanoparticles have very unique properties. Research on the properties of nanoparticles is still ongoing, and discussions will continue on whether they will be beneficial or harmful to humanity and the environment in the future. Based on these research results, we can expect that silver nanotechnology will develop more safely in the future, but we should also be aware of the potential risks of nanotechnology.
