Nanomedicine is coming for you. In a good way.
Industrial nanotechnology has already been around for a good few years: think self-cleaning paints, water-repellent clothes, glass coatings, engine lubricants, UV protection. In fact, the tiny, invisible world of nanotech has been infiltrating your life in so many ways, the natural progression is to start working its way inside you. This is a thrilling prospect indeed, offering a variety of potential treatments from tooth enamel regeneration to cancer tumour removal. At this point, nothing seems off the table.
The Nano World
Let’s first get our heads around the scale of this thing. A human hair is 80,000 nanometres wide. Now, scale that down by a factor of 40,000 and you have the double helix of DNA, at just 2 nanometres wide. That’s really, really small, isn’t it?
It’s sort of unthinkable really. You probably shouldn’t even try to get your head around it. Perhaps I’ll just delete this bit out to save you the trouble. Never mind, I’ve written it now, and it’s well known that good writers never delete what they’ve already written because it indicates lack of character*.
Quick – a distraction! Look at this exciting picture of a lost iguana exploring the nano world.
*This is not true.
How Nanotech Began
During the atomic age (aka the 1950s) the physicist Richard Feynman came up with the idea that we would eventually build things from the ground up, atom by atom. By the 1980s, Eric Drexler proposed how such nano construction could actually work.
Drexler conceived of building tiny factories with even tinier machines inside. The same decade, IBM created the first scanning tunnelling microscope (STM) with an imaging probe just one atom wide. For this, its inventors Gerd Binnig and Heinrich Rohrer won a Nobel Prize in Physics.
The impact of this technology was astonishing. Physicists could now see materials at the atomic level, enabling them to engineer a raft of nano tools for the industrial world.
What Does Nanotechnology Look Like?
To visualise nanotechnology, consider the carbon nanotube (CNT).
CNTs are allotropes (alternative forms) of carbon which take on a cylindrical structure. This gives them unusual properties, useful in electronics and optics.
Another child of the nano generation is the silicon nanowire (SiNW), capable of converting heat into electricity. Made from threads of silicone, they can be 1 nm wide and unlimited in length.
At this scale, quantum mechanical effects kick in, which has earned nanowires the pseudonym of quantum wires. Quantum wires can take the form of metallic, semiconducting and insulating wires, and can be made from both organic and inorganic molecules.
At a billionth of a metre, nanowires give us the power to engineer materials that are stronger and lighter than anything we’ve ever made before. Such nanotechnology already proliferates every manufacturing segment in the world. And now, nano researchers are turning their attention to fixing the human body with nanomedicine.
In the coming years, we’ll witness extraordinary leaps in diagnosis and treatment at the nano scale.
Let’s not forget that there are already trillions of nano devices inside your body. Your cells are minute biological factories, containing infinitesimal biological machinery that perform specific functions to grow, maintain and repair every single molecule that makes up you. When this organic machinery fails, disease takes over.
Now scientists are developing nanotools to tackle disease at the appropriate operational scale. Tools that can transport and release targeted anti-cancer drugs, without destroying healthy cells, for example. Such experiments have already proven successful in mice.
Soon, you’ll have man-made molecular machines inside you, clearing out your arteries, targeting tumours, and killing plaques in your brain. They will treat and prevent heart attacks, cancers and Alzheimer’s Disease, making such terminal diagnoses a thing of the past.
Types of Nanomedicine
There aren’t just hypothetical applications. Take a look at some existing nanomedicine tools, as well as some goals for the near future:
Contrast agents for cell imaging – Nanoparticles of cadmium selenemide (quantum dots) glow under ultraviolet light. When injected, they seep into cancerous tumours, enabling surgeons to precisely identify the boundary between the cancerous and healthy cells.
Infrared tumour removal – Gold nanoshells can detect biological markers for cancer (something you can’t do with a microscope) and bond to the affected cells. By irradiating the tumourous area with an infrared laser, the nanoshells are heated sufficiently to destroy the cancer cells.
Repairing arterial walls – During organ transplants, the accidental damage of arteries requires difficult stitching which can lead to blood leaks and other complications. By dropping gold nanoshells along the wound, an infrared laser can then weld the seam together with high precision.
Gene editing – Soon, we could employ nanobots to repair our chromosomes, switching individual genes on or off, and preventing or reversing inherited diseases like cystic fibrosis and Duchenne muscular dystrophy. This could accelerate or supplant the developing gene therapy and CRISPR gene editing applications.
Neuro-electronic interfaces – Research is underway to build nano devices that control and detect nerve impulses via an external computer. This will have considerable implications for nervous system disorders like ALS, as well as injuries and accidents that affect the nerves.
What About The Immune Reaction?
As you may have guessed, your body will react to nanobots as invaders, triggering an immune response. If we don’t address the issue, white blood cells would fight off the nano-invaders before they could get to work on diseased cells. How could we overcome this?
Nano researchers are on it. One recent study masked nanoparticles as red blood cell fragments, tricking the body into accepting them as friendly. The nanobots went on to successfully repair damaged blood vessels. With the (sometimes fatal) use of viral vectors in gene therapy trials, we’ve learned a lot about how to introduce masked invaders without triggering the immune system.
The Reality of Nanomedicine
The FDA has approved around 30 nanomedicines and 15 nanotools for use in humans. Nanomedicine applications already exist and you will almost certainly experience it in your lifetime. One day, you’ll visit your doctor with a cold and she’ll launch nanobots to seek and destroy the virus invading your body. Say goodbye to cough medicines and antibiotics: nanomedicine is on the brink of commercial use and the possibilities are endless.