Truffer, FredericBuffi, NinaMerulla, DavideBeggah, SihamVan Lintel, HaraldRenaud, PhilippeMeer, Van DerRoelof, JanGeiser, Martial2014-02-182014-02-182014-02-18201410.1063/1.4863333https://infoscience.epfl.ch/handle/20.500.14299/100956WOS:000331217300088We present a compact portable biosensor to measure arsenic As(III) concentrations in water using Escherichia coli bioreporter cells. Escherichia coli expresses green fluorescent protein in a linearly dependent manner as a function of the arsenic concentration (between 0 and 100 μg/L). The device accommodates a small polydimethylsiloxane microfluidic chip that holds the agarose-encapsulated bacteria, and a complete optical illumination/collection/detection system for automated quantitative fluorescence measurements. The device is capable of sampling water autonomously, controlling the whole measurement, storing and transmitting data over GSM networks. We demonstrate highly re- producible measurements of arsenic in drinking water at 10 and 50 μg/L within 100 and 80 min, respectively.text::journal::journal article::research article