Scientific Research Project Title

AmmoniSens Optical Ammonia Sensors for Water Monitoring

Research Institution

Aarhus University

Department of Bioscience
WATEC Aarhus University Centre for Water Technology


Chemistry, biology, environmental sciences, sensor development 


Phone +45: 3150 0741

Research leader

Klaus Koren

Assistant Professor; PhD, born 1985

I aim to develop a sensor to make real time measure of the fish toxin ammonia in aquatic environments.  

What is your project about?

In this project I will develop a new technology to measure ammonia in aquatic systems. Ammonia is a chemical that accumulates in fish cultures and is toxic for fish and the environment. Based on innovative chemistry and design it will be possible to measure the concentration of this fish toxin in real time in both freshwater and marine waters. The sensors will overcome current limitations, like cross-sensitivities, and be a long-term stable measurement device. The ambition is to bring the technology from the basic scientific development to real-world application. This sensor technology will help to increase our understanding of the nitrogen cycle, help clean water, and protect the environment. 

How did you become interested in your particular field of research?

I have always been fascinated by the fact that all living systems are based on precisely orchestrated chemical reactions. At the same time, it is extremely difficult to follow and understand those reactions in the spatial and temporal resolution needed. I therefore decided to develop tools and methods to understand better the chemical processes that underlay life. The sensors I develop help me understand the chemical environment we live in and the processes that govern it.  

What are the scientific challenges and perspectives in your project?

The use of sensors in aqueous environments faces specific challenges due to the environmental conditions such as occurring biofouling and failing sensors after short usage. The multi-layer sensor design will aim explicitly to solve present sensor problems, minimize biofouling, and increase long-term stability. This project will develop innovative sensor molecules, so called fluoroionophores, which will enable us to detect ammonia selectively. This sensor will drastically change the accuracy with which we can measure ammonia in aquatic environments and overcome present problems. In consequence, we deepen our understanding of nitrogen cycling in aquatic systems, help clean wastewater, and monitor the environment to protect fish and the ecosystem.

What is your estimate of the impact, which your project may have to society in the long term?

The tools I develop have an impact on multiple fields and enable me to widen our understanding of living systems. The project increases our basic understanding of ammonia in aquatic environments and the nitrogen cycle. Ultimately, it has the potential to result in a commercial sensor that can be used to optimize wastewater treatment and protect the environment by monitoring sensitive water masses like lakes or coastal areas.

Which impact do you expect the Sapere Aude programme will have on your career as a researcher?

The Sapere Aude grant will enable me to start an independent research group and pursue my dream of having an impact on society by pushing the limits of knowledge and technology. It will enable me to work on an exciting project for an extended period of time and to establish a stable research environment where my co-workers, students and I can follow our ideas and be creative without being too time pressed. This gives me a new freedom in my research.

Background and personal life

I was born and raised in the Austrian mountains and moved to Denmark five years ago to learn more about biology and marine environments. After spending four years in Copenhagen, I moved to Aarhus together with my wife, whom I meet in Denmark, and our dog. We expect our first child in December 2018 and are looking forward to spending our future in Aarhus. Although now far away from the mountains, my favorite hobbies are still climbing and skiing.  

City of current residence
Aarhus Kommune

High school
Stiftsgymnasium der Benediktiner in St. Paul im Lavanttal Trige