Nanomedicine: A Tiny Robot Invasion

Nanomedicine: A Tiny Robot Invasion

For years now, the tiny invisible world of nanotech has been infiltrating your life. There are self-cleaning paints, water-repellent clothes, engine lubricants and UV protection. Now, nanotech is working its way inside you, in the form of nanomedicine.

This is truly a life-changing prospect. Nanomedicine gives a variety of established and upcoming treatments - from tooth enamel regeneration, to cancer tumour removal.

At this point, nothing's off the table.

How Small is The Nano World?

Let's first get our heads around the scale of this thing.

A human hair is 80,000 nanometres wide.

Scale that down by a factor of 40,000 and you have the double helix of DNA, at just 2 nanometres wide.

Double Helix DNA

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*.

*This is not true.

Quick - a distraction! Look at this picture of a shrunken iguana lost in the nano world.

Iguana Lost in The Nanoworld

How Nanotech Began

During the atomic age of the 1950s, the physicist Richard Feynman proposed the idea that we would eventually build things from the ground up, atom by atom.

By the 1980s, the American engineer Eric Drexler proposed how such nano construction could actually work. He conceived a way to build nano factories with even tinier nano machines inside.

That 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 which are extremely useful in electronics and optics.

Carbon Nanotube

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 ever made before. Such nanotechnology already proliferates every manufacturing segment in the world.

Now, nanotech researchers are turning their attention to fixing the human body with nanomedicine.

Types of 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 machines that perform myriad functions in order 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 your body, clearing out your arteries, targeting tumours, and destroying 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.

Nanomedicine Cartoon

These aren't just hypothetical applications. Here are some examples of nanomedicines already in use:

  • Contrast agents for cell imaging. Nanoparticles of cadmium selenide (CdSe, also known as Quantum Dots) glow under ultraviolet light. When injected into the body, 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 cancerous 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.

And here are some massive up-and-coming applications for biological nanotech:

  • Gene editing. Soon, we will employ nanobots to repair our chromosomes, switch individual genes on or off, and prevent or reverse inherited diseases like cystic fibrosis and Duchenne muscular dystrophy. This could accelerate or supplant existing research into gene therapy and CRISPR gene editing.
  • 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?

Naturally, your body will react to nanobots as a tiny robot invasion and trigger an immune response. Failing to address this issue would see white blood cells fighting off the nano invaders before they could get to work on diseased cells.

How could we overcome this?

Nano researchers are on it. One 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 (occasionally 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

At the time of writing, the FDA has already approved around 30 nanomedicines and 15 nanotools for use in humans. With the huge breath of applications, a young person today will almost certainly receive some kind of nanotherapy in their lifetime.

One day, you'll visit your doctor with a pesky 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.

Rebecca Turner Bio

ABOUT THE AUTHOR: Rebecca Turner is the founder of Science Me, a biology student and a nurturer of tiny people. Read more about her story here.