• Researchers at IIT Madras have developed a unique device to detect milk adulteration; this paper based portable device can detect milk adulteration within 30 seconds.
• The device can detect multiple substances commonly used as adulterating agents including Urea, detergents, soap, starch, hydrogen peroxide, sodium-hydrogen-carbonate and salt, among others.
• Unlike conventional laboratory-based methods to test the purity of milk, which are both expensive and time-consuming, this new technology is affordable and could also be used to test other liquids such as water, fresh juice, and milkshake for traces of adulteration. Only a millilitre is needed for the test, said a statement issued by the institute. 
• The research was led by Dr. Pallab Sinha Mahapatra, Associate Professor in the Department of Mechanical Engineering at IIT Madras, along with research scholars Subhashis Patari and Driyankan Datta.
• They co-authored a research paper that has been published in the peer-reviewed journal Nature.

'Paper based portable device'

• The 3D paper-based microfluidic device is composed of a top and bottom cover and a sandwich structure middle layer. This 3D design helps transport denser liquids at a consistent speed.
• The paper is treated with reagents and left to dry. Both paper layers are then adhered to both sides of the support after drying, and the covers adhere with double-sided tape.
• Whatman filter paper grade 4 is used in this design, which allows for liquid flow and storage of more reagents.