Four scientists from CEISAM visited children in the University hospital of Nantes (CHU) as part of an initiative organized jointly by the Mission Culture Scientifique et Technique of Nantes University and the ‘School in Hospital’ program (under the authority of Nantes’s rectorat) on the 1st and 5th of June.
Ewen Bodio and Mathieu Scalabrini ran a workshop for the children entitled ‘Seeing the invisible: when children become super-surgeons!’. How can we reveal what is invisible to the naked eye? This was the question they explored with small groups of children at the hospital during a workshop on fluorescence.
The adventure began with a few experiments worthy of secret agents: writing invisible messages that could be revealed using an ultraviolet lamp, or the challenge of distinguishing a glass of water from a glass of tonic water by the beautiful bluish glow emitted by the latter under UV light. A surprising first discovery: some molecules can absorb invisible light and re-emit it in a visible form!
The young scientists then moved on to the practical applications of fluorescence. They discovered how this property can be used to check whether a room has been cleaned properly, as well as how it is used to combat fraud and authenticate official documents.
The highlight of the workshop came when the children stepped into the shoes of surgeons. Through an experiment inspired by fluorescence-guided surgery, they learnt how fluorescent molecules can help surgeons to visualize diseased tissue and guide their movements with greater precision.
It was with bright eyes – fluorescent, perhaps? – that the participants went on to make further discoveries throughout the day, ranging from virtual reality to philosophical reflection. A wonderful opportunity to show that science not only helps us understand the world, but also reveals everything that escapes our gaze.
Yann Pellegrin and Marine Letertre, for their part, discussed their research topics with several children in a ‘science dating’ session.
In the hospital wards, a discussion about river and soil pollution quickly caught the children’s attention, and they suggested solutions to tackle the problem. The first idea was to add a chemical to the water that would ‘clean’ it, but they soon realized that adding a chemical to water that was already polluted could lead to further pollution. Unless the substance were insoluble in water, like sand? In that case, it would be easy to remove it from the water by filtration. And if, on top of that, this sand was sensitive to sunlight and capable of using the energy contained in light to break down the pollutants, then we would finally have found a renewable solution for purifying the water. All this came to life when the children were able to hold in their hands a vial containing a sample of this light-sensitive sand, prepared in the laboratory, capable of removing pollutants when exposed to light. We explored this idea together with the children, their parents, and the dedicated teachers from the University Hospital who accompanied us during this wonderful afternoon of science outreach.
The children also discussed Nuclear Magnetic Resonance (NMR) and metabolomics with Marine Letertre. Naturally, the children were initially taken aback (or even frightened) by the use of these “big words”. But after drawing an analogy with the statistics used to compare the performances of two football teams – which sparked great interest among many of them – they realized that metabolomics was based on the same principle, and aimed to distinguish between the metabolism of two groups of samples using statistics. The sporting analogies did not stop there. By comparing angling with net fishing, they were able to distinguish between targeted and non-targeted metabolomic approaches. Finally, they grasped the main principles of NMR, the analytical chemistry tool that enables us to carry out metabolomic studies in the laboratory. They imagined that the nuclei of the atoms that make up matter dance chaotically in their natural state, and that the application of a magnetic field generated by a huge magnet enables these nuclei to perform a well-coordinated dance. These discussions enabled the children and their parents to engage with this complex research topic, and they showed their curiosity by asking numerous questions, leading to rich and highly rewarding discussions.