Jérôme LAUNAY, 42 years old, received the Engineering degree in electronics and microelectronics from the French "Institut National des Sciences Appliquées de Toulouse" (INSAT, France) in 1998 and his Master degree in microelectronic from the INSAT in 1998. He joined the French "Laboratoired'Analyse et d'Architecture des Systèmes" (LAAS) from the French "Centre National de la RechercheScientifique" (CNRS) in 1998 and received the PhD degree from the INSAT in 2001.Since 2006, as a lecturer at LAAS, he has been working on the integration of materials for microtechnological applications as well as on the study of physical, chemical and biological microsensors. His expertise field involves the technological integration and the study of bio-electro-chemical detection/transduction principles for the aqueous phase analysis at the microscale, aiming to health, environment and agri-business applications. His research interests concern the realisation of bio-electro-chemical microsensors, the integration of pH-metry techniques, the detection of bio-electro-chemical species in real media, the monitoring of cells cultures and/or single cell analysis.
The present work was dedicated to the development of a lab-on-chip device for water toxicity analysis and more particularly herbicide detection in water. It consists in a portable system for on-site detection composed of three-electrode electrochemical microcells, integrated on a fluidic platform constructed on a glass substrate. The final goal is to yield a system that gives the possibility of conducting double, complementary detection: electrochemical and optical and therefore all materials used for the fabrication of the lab-on-chip platform were selected in order to obtain a device compatible with optical technology. The basic detection principle consisted in electrochemically monitoring disturbances in metabolic photosynthetic activities of algae induced by the presence of Diuron herbicide. Algal response, evaluated through oxygen (O2) monitoring through photosynthesis was different for each herbicide concentration in the examined sample. A concentration-dependent inhibition effect of the herbicide on photosynthesis was demonstrated. Herbicide detection was achieved through a range (blank – 1 µM Diuron herbicide solution) covering the limit of maximum acceptable concentration imposed by Canadian government (0.64 µM), using, for the stimulation of algal photosynthetic apparatus, an organic light emitting diode (OLED), having an emission spectrum adapted to algal absorption spectrum and assembled on the final system.