The phrase “there’s plenty of room at the bottom” penned by Physicist Richard Feynman in 1959 is considered as the spark that ignited interest in nanotechnology. Using this idea, he imagined the manipulation of individual atoms to create new or altered material. Whilst these were bold ideas for that time, they weren’t entirely new.
The alchemists of the Medieval Age understood that metallic nanoparticles mixed into glass created different shades and colours and used them to make the beautiful stained-glass windows of European medieval cathedrals. Similarly, ‘Damascus steel’ made by creating special carbon formations called nano-tubes inside the steel created strength, sharpness, and shatter-resistant blades. This very specific carbon content and manufacturing method was used by the Middle-Eastern metalsmiths for centuries and it still considered one of the strongest materials around.
Since these, and many other early examples of nanotechnology were created, we have slowly begun to understand the potential of this technology and how it could change how we live and work.
Nanotechnology refers to the use of scientific principles to create something useful or practical. The term ‘nano’ derives from ancient Greek, meaning ‘dwarf’. In modern day, nano refers to a length scale of one billionth of a meter. To put this into context, the width of a single hair is 80,000 nanometres, so a nanometre is to a meter, what a small marble ball is to planet Earth. Nanotechnology, therefore, is the manipulation of scientific laws and principles at the nano scale to develop useful applications.
It is fair to say that trial and error has historically been the main driver for nanotechnology discoveries, but we are now at a level of development where we understand that a material in its bulk form will exhibit different properties to that same material at the nano scale. This, in addition to our ability to image, alter and probe these nano-scale formations, allows us to consciously and systematically study them in depth.
Research into the properties of nano-scale materials has taken place in parallel with the quest of miniaturisation and as a result, the two endeavours have gone hand-in-hand to unfold a host of new ground-breaking applications. For example, off-the-shelf sunscreen creams contain titanium oxide or zinc oxide nanoparticles as they absorb ultraviolet light and prevent skin damage, and in a quest to develop new manufacturing paradigms, nanotechnology applications in printing have become mainstream. Silver and gold nanoparticles suspended in liquids create conductive printable inks that can be manufactured cheaply and facilitate connections and interconnects in electronic circuitry. In fact, these inks are beginning to become key to solar cell technologies.
The automotive industry has also become an early adopter of nanotechnology-based printing technologies, using conductive inks to print window demister lines on automobile windscreens for many years. They are also being applied to clothing. A company called Rhone, has integrated gold and silver nanoparticles into their designs to prevent odours and introduce anti-microbial benefits.
Perhaps the most intriguing application of nanotechnology is within the field of medicine. When the human body becomes ill it begins to give indicators that there is a problem in the form of ‘biomarkers’ – genes, proteins or hormones. Nanoparticles allow unprecedented accuracy and resolution in detecting these biomarkers in tiny amounts, facilitating early stage diagnosis, critical for higher healing chances.
Test strip sensors based on integrated specialised nanoparticles can detect these biomarkers, allowing diagnosis in hospitals to be transferred to comfort of the patient’s home. This technology makes illness detection much more accessible and less costly to healthcare providers. The commercial implications to pharmaceutical companies and cost savings on national health systems are immense.
In the fight against cancer, nanotechnology is leading the charge. By carefully engineering gold nanoparticles to bind and interact with pre-defined proteins, cancerous cells can be singled out. This allows the treatment team to image their composition more accurately aiding treatment strategy and, more importantly, making the delivery of medication much more discriminate, preventing damage to other healthy parts of the body, as is the case with chemotherapy. These developments have triggered research into ‘nano-robots’ which could be guided in the body and locally fulfil a defined task across a wide range of disease and illnesses, changing how we approach and treat medicine.
Nanotechnology is likely to appear in our everyday lives more and more. Here, we have merely scratched the surface of the potential of nanotechnology highlighting creams and cosmetics, manufacturing, health and clothing as just a few industries that are already fully integrating the technology into their operations. However, it should come as no surprise that solutions to some of the world’s most pressing issues, such as global warming, will find resolutions within the realm of nanotechnology, and this is a very exciting prospect.