Light emitting devices and integrated electrochemical sensors on lab-on-chip for toxicity bioassays based on algal physiology

In the frame of water toxicity analysis, a portable, glass-based, lab-on-chip was developed, integrating threeelectrode electrochemical microsensors and organic lightemitting diodes (OLED). The basic detection principle consists in monitoring electrochemically O2-related, algal metabolism in presence of herbicides. Thus, aiming on Diuron herbicide detection, a concentration-dependent inhibition effect on photosynthetic oxygen production rate was evidenced in the [0 - 1 µM] range. Finally, OLEDbased integrated system demonstrates higher detection characteristics than those using external white light source (sensitivity: 0.48 versus 0.26 nA/s/µM) and is highly promising for further integration of optical and electrochemical sensors enabling double complementary detection.