Introduction

Introduction

Every second, our bloodstream carries oxygen, nutrients and drugs to every corner of the body. But not all drugs reach the right destination. Chemotherapy drugs, for example, often circulate throughout the body, attacking both healthy and cancerous cells. This causes painful side effects and limits the effectiveness of treatment.

Now imagine if drugs could travel like guided missiles: tiny vehicles programmed to deliver drugs only where they are needed. This is the promise of nanomedicine, a field that applies nanotechnology (which operates on a scale of billionths of a metre) to healthcare. Nanoparticles can be designed to move through the body, evade natural defences, and deliver treatments directly to diseased cells.

In this learning unit, students will embark on a journey into the invisible world of nanomedicine delivery. First, they will explore the fundamentals of science and medicine at the nanoscale, then carry out interactive missions in an augmented reality (AR) laboratory where they will guide nanoparticles through the human body, and finally, enhance their understanding by reflecting on the possibilities, challenges, and ethics of this revolutionary technology.

Nanomedicine uses structures so small that a thousand of them lined up would be thinner than a human hair. At this scale, materials behave in unusual ways. For medicine, this represents a sea change. Nanoparticles can be designed to carry drugs like tiny capsules, targeting diseased cells with much greater precision than traditional methods.

The importance of this technology lies in its potential to transform the way we treat disease:
In cancer therapy, nanoparticles can recognise cancer cells and deliver chemotherapy directly to them, sparing healthy tissue.

In neurology, some nanoparticles can cross the blood-brain barrier, a natural barrier that normally blocks most drugs, opening up new avenues for the treatment of brain diseases.

In infectious diseases, nanomedicine is already being used in the administration of mRNA vaccines against COVID-19, where lipid nanoparticles protect and safely transport fragile genetic material into cells.
By solving the problem of drug delivery, nanomedicine not only promises more effective treatments, but also a reduction in suffering by minimising harmful side effects.

What are nanoparticles?

A nanoparticle is an extremely small particle, measuring between 1 and 100 nanometres. To give you an idea, a nanometre is one billionth of a metre. If you were to cut a single human hair into 100,000 pieces, one of those fragments would be roughly the size of a nanoparticle (TWI Global, 2023).

At this microscopic scale, materials often behave very differently from their larger, bulkier forms. For example, gold, which normally appears shiny and yellow, can appear red or purple when reduced to nanoparticles due to the way it interacts with light. Nanoparticles also have a very high surface-to-volume ratio, making them much more reactive and useful for chemical, biological, and technological applications (PNNL, 2023)

In medicine, nanoparticles are particularly important. They act as microscopic transport vehicles for drugs. Scientists can design them to:

• travel safely through the bloodstream,
• avoid destruction by the immune system,
• attach specifically to diseased cells (such as cancer cells), and
• release drugs in a controlled manner only at the site of the disease.

This ability to deliver treatments with such precision is why nanoparticles are fundamental to nanomedicine. For example, lipid nanoparticles have been essential for transporting the fragile mRNA used in COVID-19 vaccines. Similarly, researchers are testing nanoparticles that can cross the blood-brain barrier, opening new doors for the treatment of neurological diseases (NIH, 2022).