A student in the UK has designed a miniature, mobile refrigerator that can fit inside a backpack to easily transport medical supplies and vaccines to people in remote areas.

The portable device has been shown to keep vaccines at an optimal temperature for up to 30 days, and if it lives up to its potential, health experts have predicted that it could help treat more than 1.5 million people around the world.

"I make things every day for people who have everything," the inventor, Will Broadway, told Michael Baggs from the BBC.

"I wanted to make something for people who have next to nothing. It should be a basic human right, in my opinion, to have a vaccination. I don't think that it should be patented to restrict use."

Right now, getting vaccines to people in developing countries in Africa and parts of Asia relies on something called the 'cold chain transport' - a type of supply chain where goods are kept at very precise temperatures while in transit by making a series of stops along the way.

The problem with this system is that many developing countries and remote regions don't have proper cold chain supply lines in place, because their roads and electrical systems are unreliable.

This means that many vaccines and other medical supplies run the risk of hitting unsafe temperatures in transit, rendering them useless by the time they reach their destination.

"Blood donations, organ transplants - if they get stuck in traffic, you still use cold packs that really aren't adequate for long periods of time," Broadway, who is currently studying at Loughborough University in England, told the BBC.

After noticing these flaws during a trip to Cambodia in 2012, Broadway went about developing a device that would keep vaccines and other supplies at a proper temperature for the duration of the trip, skipping all the stops that a normal vaccine transport route would take.

He came up with a mini refrigerator - which he's named the Isobar Cooling Tank - that creates ammonia vapours by heating ammonia and water. As the BBC explains, this gas is released when needed inside the chamber, keeping the contents inside to just above freezing for 30 days straight.

The device works because when the ammonia and water are heated, they separate inside the cooling tank. Then, after getting separated, these two substances can be reintroduced to each other, which triggers a cooling effect - known as absorption refrigeration - that can be controlled by how much water and ammonia are allowed to interact.

Broadway says he envisions the device as a way to transport organs and blood in the future, though right now his focus is on vaccines. 

Going forward, he says he wants to be involved in the production of the device to ensure that it's working the way he intended.

"I would be hands on, all the way through it, knowing that it works," he told the BBC. "It's amazing to just give it a go, even in my backyard, and see the potential of the technology."

So far, there's no word when the Isobar Cooling Tank will start seeing actual use, but given the amount of attention it's garnered, and the possibilities it offers, hopefully it lives up to its promise and makes a real difference for those in need of better access to medications in the future.