BITS-Pilani Hyderabad team unveils sensor to detect heavy metals in water in 2 minutes

A research team of the BITS Pilani Hyderabad campus, MEMS, Microfluidics and Nanoelectronics (MMNE) Lab has developed an on-site multiple heavy metal detection tester for water quality assessment where quick results can be delivered within just two minutes enhancing efficiency in monitoring.

The innovation enables on-site testing, significantly reducing the burden on laboratories when they get large volumes of contaminated samples. This cost-effective solution offers good accuracy, repeatability, and reproducibility when compared to traditional lab-based testing methods, said Dean and Professor Sanket Goel on Wednesday.

IISc researchers come up with solutions to reduce presence of heavy metals in groundwater

The sensor, constructed using carbon threads and modified, is designed to quantify cadmium, lead, copper, and mercury in water samples, operating on electrochemical principles for accurate and reliable detection. It has been tested on lake samples around Hyderabad, including Hussainsagar Lake, Kapra Lake, and Shamirpet Lake where the water quality results had confirmed that the heavy metal concentrations were within permissible limits, he said.

Others involved in the study are: R.N. Ponnalagu, Sreerama Amrutha Lahari, Nikhil Kumawat, Khairunnisa Amreen and PhD student Amrutha Lahari.

While the established pattern of testing water quality using plasma-mass spectrometry, high-performance liquid chromatography and atomic absorption spectroscopy are expensive due to sophisticated instruments requiring skilled operators, here costs can be reduced.

The ability to miniaturise the system allows convenient point-of-source testing with simplified sample preparation. The sensor also underwent extensive testing to assess its performance under various conditions, including its response to different pH values, ability to function in the presence of other heavy metals, and in analysing real water samples from various lakes, said Mr. Goel.

Researchers have also integrated Artificial Intelligence (AI) through a Convolutional Neural Network (CNN), to enable qualitative analysis of contaminants with greater clarity and accuracy. Incorporation of the Internet of Things (IoT) technology makes it real-time, allowing remote water quality monitoring, thus enhancing accessibility and efficiency. This ‘intelligent’ system ensures seamless, user-friendly detection of heavy metals, making advanced water quality analysis more practical and widely available, he pointed out.

The study has been published in npj Clean Water, a leading environmental research journal and is supported by Anusandhan National Research Foundation (ANRF), India.

90% waste treatment

Another team of researchers Atun Roy Choudhury and Sankar Ganesh Palani of the institute have developed a Sandwich Aerobic-Anaerobic-Aerobic (SAAnA) system, a patented technology that achieves over 90% waste treatment efficiency while reducing water usage and maximizing biogas and compost production.

This innovation accelerates waste processing, enhances energy recovery, and offers a cost-effective, sustainable solution to growing solid waste challenge in the country. The reactor patent has also been selected by the Central Government under the prestigious ‘Kapila Scheme’, said a press release.