Autonomous microfluidic system to measure arsenic in drinking water based on fluorescence detection

Arsenic (As) in drinking water is a non-negligible problem and affects over 137 million people in more than 70 countries [1]. The aim of this project is to use nonpathogenic Escherichia coli (e. coli) that produce a green fluorescent protein (GFP) after exposure with As. 10μg/L is the maximum As concentration in drinking water recommended by the US-EPA environmental protection agency and the WHO. Challenges are to minimize all lab equipment usually needed around the small microfluidic polydimethylsiloxane (PDMS) block, especially the large fluorescence microscope, which is to be replaced by a small optical arrangement to collect the light from the GFP and detect it with a high SNR. A portable system to measure arsenic in low concentrations smaller than 10μg/L is presented and results are shown.