Grant of €700,000 to gain better understanding of nitrogen dioxide with GELSONDE

Nitrogen dioxide (NO₂), a gas emitted by industry and traffic, is a major contributor to nitrogen deposition in the Netherlands, alongside ammonia, which is emitted mainly by the agricultural sector. Unfortunately, NO₂ is not easy to measure, not on the ground, and certainly not high in the atmosphere. Although there are NO₂ meters, these meters also measure a variety of other gases, making the readings unreliable.

Portable lab

KNMI, which measures NO₂, would like to take better, more precise measurements than they are able to do at present, says Kouwer. “For their measurements in the atmosphere, they use weather balloons, but the sensors often break down in the process. NO₂ is quite easy to measure in a lab situation, so what you actually want is some kind of portable lab setup, which can be placed in one of these weather balloons.”

This will soon be possible, thanks to the NWO-OTP grant. The GELSONDE project brings together a team of materials chemists and sensor specialists who are joining forces to create a new, low-cost, and portable sensor. Kouwer: “In my lab, we are developing the materials and molecules that will make NO₂ visible. Think of a fluorescent signalling material in a gel. We are working with Simona Cristescu's group, who are experts in measuring those signals. Our other partners are helping us to build a prototype that we will test in a KNMI weather balloon. Our objective is to be able to deploy our new sensor widely, in business parks, at events, and high in the atmosphere, so that we can accurately measure NO₂ concentrations anywhere.”

Practical prototype

The grant makes it possible to fund a PhD candidate for Kouwer's lab and a postdoc for Cristescu's lab. The NO₂-signaling gel should be as sensitive and as stable as possible. The process of reading the fluorescent signal from the gel will also be refined further. Kouwer: “Together with our partners, we will use the next four years to create a prototype that is usable in practice, stable, convenient, and affordable. In the process, we will obviously also keep in mind that a similar device could be used to measure other gases than NO₂.”

The GELSONDE project partners are:

• Paul Kouwer, Synthetic Organic Chemistry, Radboud University 
• Simona Cristescu, Life Science Trace Detection Laboratory, Radboud University 
• The Royal Netherlands Meteorological Institute (KNMI) 
• SensorSense 
• Intemo 

Photo: chris robert via Unsplash