LAWC
Duration: 24 months, Start: January 2016
Academic project leader: Jean-Pierre Wolf, Institution: GAP Biophotonics, University of Geneva. Industrial project partner: Tibio Sagl.The supply of high quality drinking water is a major safety and health concern. Pollution of drinking water is associated with two major families of contaminants: microbial and chemical. Polyharomatic hydrocarbons (PAHs), whose origin is both natural (forest fires) and anthropogenic (fossil fuels combustion, waste incineration, etc.), are a particularly insidious group of chemical organic contaminants. Beside the atmospheric route, they might be introduced in potable water infrastructure via water treatment plants and rainwater collecting basins. The identification of PAHs in water is normally based on liquid and gas chromatography combined with mass spectrometry or optical detection (absorption and fluorescence) in the ultraviolet. As for biological pathogens, public water analysis is performed following standardized ISO methods largely based on surface plating and membrane filter techniques. All these approaches are associated with relative long incubation times necessary for performing the final assessments: a major limiting factor for both sampling volume and sampling frequency. On the other hand, fluorescence-based optical techniques are faster but they sorely lack in specificity as the spectral properties of PAHs and water bio-contaminats are very similar.
With this project, we aim at setting-up a real-time, portable, and totally consumable-free optical system operating on a liquid jet that can be easily derived from the water distribution infrastructure. The selective identification of bacterial against organic pollutants relies on an innovative pump-probe laser scheme developed and patented by Jean-Pierre Wolf’s group at the University of Geneva. The basic principle is a straightforward application of NCCR MUST core expertise, as it uses short (nanosecond) laser pulses to interact with multiple electronic states of the molecules contained in the pollutants. The optical response is then used to precisely define at which family the molecules interrogated belong, overcoming most of the limitations of standard optical approaches based on a single laser interaction. The project is run in collaboration with TIBIO, a Swiss SME active in the field of environmental monitoring and water decontamination.
Back >>