Scientists at a Pune lab have found a way of producing cheap and clean drinking water from contaminated water by using a membrane as filter. The device does not depend on electricity as most other water filters do and can thus be used in remote rural areas as well as disaster zones. The breakthrough was made at the Pune-based National Chemical Laboratory's polymer division and the new technology was granted a US patent earlier this year. NCL then transferred the knowhow on a royalty basis to Pune-based entrepreneur Subhash Devi, who has since marketed the water filter. It is now available in the market under the brand name Purion.