By: IPP Bureau
Last updated : August 07, 2026 8:08 am
Beyond water quality monitoring, E-Eye can also analyse toxicants in environmental and biological samples, vegetables, food products, tea, herbal products, soil and milk
Researchers at the Indian Institute of Technology (IIT) Guwahati have developed a portable optical sensing device capable of instantly detecting multiple toxicants in water and other biological samples, offering an affordable solution for real-time water quality monitoring.
The innovation, named E-Eye, has been designed as a portable point-of-care testing device, E-Eye functions as an electronic eye that detects multiple toxicants on-site with high accuracy and wirelessly transmits the recorded data to water treatment facilities for monitoring and analysis.
The research findings have been published in the IEEE Sensors Journal in a paper co-authored by Prof. Tapas K. Mandal and Prof. Harshal B. Nemade along with researchers Shrikant Kashyap, Smriti Sachan, Neha Majee, Maitrayee Bhuyan and Humayun Kabir.
The device operates through a chemical reaction that produces a coloured compound, with the colour intensity corresponding to the concentration of toxicants. Using optical sensing principles, E-Eye converts this information into digital data and displays the concentration of contaminants in real time.
Unlike conventional laboratory-based instruments such as UV-Visible spectrophotometers and Atomic Absorption Spectrophotometers (AAS), the portable device can be deployed directly at the source of water contamination while delivering comparable analytical accuracy. It also offers digital integration capabilities for efficient monitoring.
Prof. Tapas K. Mandal, Professor, Department of Chemical Engineering, IIT Guwahati, said, "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."
The researchers said the device has been developed at a cost of approximately Rs. 3,500, while the cost of testing each sample is around Rs. 2, making it a cost-effective alternative for large-scale deployment. The manufacturing cost is expected to decline further with industrial-scale production.
Beyond water quality monitoring, E-Eye can also analyse toxicants in environmental and biological samples, vegetables, food products, tea, herbal products, soil and milk. The research team has evaluated more than 2,700 samples using the device and reported accurate results.
Prof. Harshal B. Nemade, Professor, Department of Electronics and Electrical Engineering, IIT Guwahati, said, "E-Eye has prominent application potential across government departments, industries, and private enterprises. It can support agencies under the Ministry of Jal Shakti in water quality monitoring, assist food and herbal product manufacturers, and help industries monitor liquid effluents containing heavy metals, bacteria, and odor-causing compounds."