IIT-G develops low-cost device to detect toxic metals, bacteria in water

IIT Guwahati researchers develop portable device that quickly detects toxic metals in water

NEW DELHI: Researchers at IIT Guwahati have developed a portable optical sensing device that can quickly detect toxic metals, fluoride and bacteria in water samples, offering a low-cost tool for on-site water-quality checks in rural areas and places without easy access to laboratories.Named E-Eye, the device has detected arsenic, lead, iron, chromium, fluoride and Escherichia coli bacteria during laboratory tests, the institute said on Thursday. The estimated cost of the device is about Rs 3,500, with each sample test costing around Rs 2.The device uses a chemical reaction that produces a coloured compound. The intensity of the colour changes according to the concentration of the contaminant. E-Eye analyses the colour through optical sensing, converts the reading into digital data and displays the concentration of the toxicant.According to the researchers, the portable system can be deployed directly at water sources, unlike conventional testing equipment that generally requires samples to be taken to laboratories. It can also wirelessly transmit test results to water-treatment facilities.The team said E-Eye’s results were comparable with those obtained through standard UV-Visible and Atomic Absorption spectrophotometers. More than 2,700 samples have been tested using the device, it added.“The device operates on the Beer-Lambert law and combines optical sensing with digital electronics to generate accurate quantitative measurements. Our device has been able to successfully detect toxicants such as arsenic, lead, iron, chromium, fluoride, and Escherichia coli bacteria,” said Tapas K Mandal, professor in IIT Guwahati’s department of chemical engineering.The researchers said the device could support water-quality monitoring under the Centre’s Jal Jeevan Mission, which seeks to provide tap water to rural households while ensuring that the water supplied is safe.Apart from drinking water, E-Eye can be used to test environmental and biological samples, vegetables, food products, tea, herbal products, soil and milk, the institute said. It may also help industries monitor liquid effluents containing heavy metals, bacteria and odour-causing compounds.

The research, supported by a grant from the ministry of electronics and information technology, has been published in the IEEE Sensors Journal. The team includes IIT Guwahati professors Mandal and Harshal B Nemade, along with researchers from the institute, KIIT Bhubaneswar and Ramakrishna Mission Residential College, Kolkata.The researchers have set up ENVIONIX Labs Pvt Ltd to commercialise the technology and are exploring an industry partnership for its transfer. They are also working to integrate solar panels and cloud connectivity into the device for remote monitoring and data management. Go to Source