Read the full article by Nathan Kilah (Cosmos)

“Colour and chemistry have always combined quite closely for me. When I went to university, I was uncertain what sort of science I wanted to do, but in second year I started to learn about the transition metals that give us a whole realm of beautifully coloured compounds. That led me to being an inorganic chemist, interested in metals. And I guess it informs the fact that I’m now trying to make a colour-based sensor to detect PFAS – per- and polyfluoroalkyl substances

…Everywhere we go in the world, we find contamination. But by understanding what is out there and how it can affect us, we can make better choices about how and where we live our lives. The goal with my PFAS work is to create a simple colour-change test that everyday folk can use…

…But one of the bigger uses is in so-called aqueous fire-fighting foams, or AFFFs. These are the big foam suppression systems used in aviation fires, or industrial fires, where pumping out lots of foams helps put out fires very efficiently.

The problem is that these fire-fighting training grounds or fire sites have had a heap of these PFAS molecules dumped onto the ground, where they can move through the landscape and into the water table. The wonderful chemical properties that allow PFAS to do what they do is based on the carbon-fluorine bonds, but there aren’t natural pathways for those molecules to be broken down, so this leads to these molecules being very persistent in the environment.

This way they can come into contact with people through either their food or water supply. The full health impacts of these PFAS are not known – there’s a lot of work to be done around the consequences of PFAS exposure. But we do know that they accumulate in people, and there are about six health conditions (so far) that have been identified as having firm links with PFAS exposure…

…The normal way of testing for these substances involves around half a million dollars’ worth of equipment, usually liquid chromatography-mass spectrometry, which is probably located in a lab that’s hundreds of kilometres away from the actual site of contamination. It’s very expensive and very costly in time to run these tests.

We want to create a simple PFAS test that anyone can use. The basis of our colour-change idea is that we have built a molecule, which is like a little basket for the most common PFAS. And when the PFAS enters the basket, it changes the chemical properties of the basket, which leads to a change in colour. The two molecules can interact with each other without actually undergoing a chemical reaction that sticks them together. This is often referred to as ‘host-guest’ chemistry, where the ‘host’ molecule is the thing that we’ve made, and the ‘guest’ is the PFAS.

We’ve been able to demonstrate this change in colour in laboratory testing, and we’ve protected the work that we’re doing with a patent. The ‘next big thing’ is taking that scientific concept and laboratory activity and transitioning it into a product – something that can be used for a particular problem case, testing soil, say, or water, or perhaps blood.

The big challenge now is linking the fundamental science that we have and pairing up with companies to develop it into something that could be useful in the field.

People are interested, definitely. I’ve had conversations with government agencies and a number of companies. We’re looking to build those networks and understand the gaps where we can most readily apply this technology to real-world problems.”…