Ultra weak photon emission of water
Assessing ultra-weak photon emission as a marker of treatment-induced changes in water
Ultra-weak photon emission (UPE) is a very weak light signal that has been measured in many biological systems and is mainly linked to oxidative and physicochemical processes. In water systems, however, spontaneous photon emission remains poorly understood and experimentally challenging. This project investigates the origins of UPE and whether and how these signals are related to physical, chemical or microbiological parameters. The project further investigates the applicabilty of UPE as detection tool for non-chemical water treatment methods. Measurements will include ultra-sensitive photon counting, delayed luminescence, dynamic light scattering, zeta potential, flow cytometry and microbiological profiling. The project combines photonics, water technology and microbiological analysis to create a scientifically controlled framework for evaluating treatment-induced changes in water.
Research challenges
The main challenge is that ultra-weak photon signals from water are extremely small and can easily be influenced by detector background, impurities, dissolved gases, microbial activity, bubbles or container effects. Existing studies are fragmented and often difficult to reproduce. The project therefore needs a highly controlled measurement workflow with strict dark conditions, matched controls and orthogonal analytical methods. Another challenge is distinguishing whether possible optical signals originate from physical water properties, chemical reactions or microorganisms. Dynamic light scattering and zeta potential are matrix-sensitive and require careful interpretation. The project must also determine whether any observed treatment effects are reproducible rather than artefacts of handling or environmental conditions. By integrating optical, physicochemical and microbiological measurements, the project aims to establish a robust feasibility framework for future high-tech water analysis applications.
Your assignment
You will help develop and apply a multidisciplinary experimental workflow to investigate ultra-weak photon emission from water. You will perform optical measurements using photon-counting systems, assist in delayed luminescence experiments and analyze treatment-induced changes in water samples. You will also contribute to physicochemical measurements such as pH, conductivity, dissolved oxygen, dynamic light scattering and zeta potential analysis. In collaboration with project partners, you will support microbiological analyses including flow cytometry and advanced microbial profiling. You will process and interpret experimental data, compare treated and untreated samples and evaluate whether observed optical signals can be linked to physical, chemical or biological mechanisms. Your work will contribute directly to the development of new high-tech analytical approaches for water research.
Your profile
You will have a background or strong interest in physics, chemistry, photonics, water technology, biotechnology or microbiology. You will enjoy experimental laboratory work, interdisciplinary research and data analysis. You will be motivated to work independently while collaborating in an international applied-research environment.
Keywords: Biophotonics; delayed luminescence; water technology; colloidal analysis; photon counting
Professor/University group/Wetsus supervisor(s):
Promotor: Prof. dr. Aard Nederveen, UvA
Co-promotor: Prof. Dr. Astrid Paulitsch-Fuchs, Med-Uni Graz
Co-promotor: Prof. Dr., Institute of Photonics and Electronics of the Czech Academy of Sciences
Wetsus supervisor: Elmar C. Fuchs, Xiaoxia Liu
Project partners: Applied Water Physics
Only applications that are complete, in English, and submitted via the application webpage before the deadline will be considered eligible.
Guidelines for applicants: https://phdpositionswetsus.eu/guide-for-applicants/
