About our writer
Naomi Foster is in her second year studying Engineering Science at St. Anne’s College, Oxford. Naomi was a Mentor for Cambridge Immerse in 2017.
This month, Tokyo will host the 17th edition of Nano Tech – an international exhibition and conference on nanotechnology. This year’s exhibition will feature research covering subjects from AI to cancer research, and aerospace to the environment. So what is nanotechnology, and how can it be a part of this wide variety of fields?
Nanotechnology is technology of very small things, typically on the scale of 1-100 nanometres. To give you an idea of how small this is, if a marble were a nanometre, then one metre would be the size of the Earth.
It’s quite a recent technology – before we had scanning electron microscopes (the kind of microscopes which can view things on an atomic scale) we couldn’t see things on a nanoscale, let alone make them.
How did it begin?
In 1959 Richard Feynman, the famous physicist, gave a talk entitled “There’s Plenty of Room at the Bottom”, where he put forward the idea of manipulating individual atoms and molecules, and talked about the possibilities this would present. At this time, it was just an idea, and it stayed this way until the scanning electron microscope was invented in 1981.
This signalled a huge change in our abilities to do things on a tiny scale, and soon we were making astonishing creations.
In 1985, a joint research project between the University of Sussex and Rice University was taking place, aimed at identifying interstellar matter. As part of their experiments, the scientists were vaporising a carbon rod, and noticed that C60 (a molecule made of 60 carbon atoms) was forming, in spherical shapes.
This completely rewrote the current understanding of the chemistry of carbon. Previously, it had been thought and taught that carbon can take two forms – it’s either found as graphite or as diamond. These scientists had just discovered a whole new form of carbon, completely by accident.
The structures they’d found are commonly known as “Buckyballs” and were the first “fullerenes” to be created. Now, many more have been made – tubes, ellipsoids and loads of others.
Buckyballs have lots of uses – the hollow shape of the balls means they can encase other atoms which can be useful as a delivery system. There are hopes they could be used to carry radioactive elements into the body and deliver them to cancerous tumours.
Fullerenes have also been used in lubricants, electronics, superconductors and countless other applications.
Nanotechnology is a really new science, still taking its first baby steps. No one can really say where it will go next although there have been a range of predictions – maybe we’ll be able to make pencils into diamonds, or maybe self-replicating nanorobots will take over the world! However, there are some exciting developments happening as we speak.
A team of researchers from the University of Southampton made headlines recently after making a highly successful alternative to a transistor, called a memristor, using nanotechnology.
Transistors are the building blocks of all computing, found in huge numbers on circuit boards called chips in every digital device. Over the years, transistors have been getting smaller and smaller, allowing us to improve our technology time and again by putting more transistors on each chip. However, we are now reaching the physical limit of how small we can go – you can’t make anything smaller than an atom.
The memristor heralds a new step forward – whereas a transistor can either be on or off, a memristor can hold up to 128 different states at once! This could allow future computers to reach blistering speeds we can only dream of.
The team managed this amazing feat by layering metal-oxides on the nano-scale and experimenting with different combinations of metals within the memristor.
One of the most interesting areas nanotechnology has been applied to is medicine. As technology improves, there is a drive (and an ability) to move towards regular tracking of patients with ongoing conditions to help them manage their health over the long term.
Diabetes is a condition where the body can’t control the levels of sugar in the blood and affects millions in the UK alone. Diabetics have to check their blood sugar levels regularly to make sure they don’t get too high or low. At the moment, this involves pricking the skin and drawing blood, which can be unpleasant and time-consuming. People often avoid checking their blood sugar levels because of this – which can lead to them getting seriously ill.
A study on a wearable blood glucose sensor was recently published in the journal ACS Nano – the sensor could be part of a contact lens or watch and could detect levels of blood sugar through the sweat or tears.
Using nanoribbons of indium oxide, the researchers made a biosensor by trapping an enzyme in the nanostructure. When glucose was present, the enzyme would react with the glucose and make a tiny electrical signal. The intensity of the overall signal, gives the sensor a good idea of how much glucose is present, and can be used to continually and painlessly track a patient’s levels.
The sensor has been found to be sensitive enough to pick up data from tears, sweat and saliva, in people with and without diabetes. It is also hardy – it can cope with being bent back and forth 100 times.
This incredible technology could change the lives of many diabetics, and lead to fewer people needing emergency treatment.
An exciting future
It will be interesting to see where nanotechnology takes us next – it really is the stuff of Sci-Fi. There are still some worries about the safety of nanoparticles, as it is such a new technology with research still ongoing. However when these concerns are allayed, we can expect big growth in this sector – as Richard Feynman said “There’s plenty of room at the bottom”.