IIT Guwahati's E‑Eye device enables rapid detection of water toxins

Researchers at the Indian Institute of Technology Guwahati have created a portable optical sensor called E‑Eye that can instantly identify a range of toxic substances in water and biological samples. The device uses a chemical reaction that produces a coloured compound, with colour intensity indicating the concentration of contaminants such as arsenic, lead, iron, chromium, fluoride and Escherichia coli. It operates on the Beer‑Lambert law, converts the optical signal to digital data and transmits results wirelessly to water‑treatment facilities.

E‑Eye is designed to support India’s Jal Jeevan Mission, which aims to provide safe tap water to every household. Laboratory tests show the sensor’s accuracy matches that of conventional UV‑Visible spectrophotometers and atomic‑absorption instruments, while costing roughly Rs 3,500 for the unit and about Rs 2 per test. The research findings were published in the IEEE Sensors Journal and co‑authored by Prof Tapas K Mandal, Prof Harshal B Nemade and a team of graduate scholars from IIT Guwahati, KIIT Bhubaneswar and Ramakrishna Mission Residential College, Kolkata.