Engineering the future of safe water supplies
Environmental engineers have created a substance which can produce safe, drinkable water by easily killing off bacteria in seconds.
The incredible creation was made by a team of material scientists and environmental engineers from Singapore and the United States, who began work after the devastating impact of the 2004 Indian Ocean Tsunami on the safety of drinking water supplies.
The engineers have come up with a porous gel-like substance which uses silver nanoparticles to rapidly annihilate any potential pathogens on contact.
The lethality of this form of silver was one of the main hurdles for the collaborative team, which faced the task of creating a solution which would allow the silver to destroy pathogens without contaminating the water or drinker.
The goal was achieved by immersing the polymer gel in water at very low temperatures, forcing tiny pockets of ice to form within the material, leaving it riddled with pores. It was then immersed in sodium borohydride to cover the gel’s pores with tightly-bound nanoparticles.
Initial tests have shown the material can destroy E. coli and grass bacillus to a mere 0.1 per cent of their original levels within just a few seconds of contact, all while keeping concentrations of bio-available silver in water well within World Health Organisation safety limits.
Four grams of the pathogen-destroying polymer can absorb purify up to half a litre of water with almost no effort. The material could be dropped into disaster zones for sufferers to use by simply dunking in contaminated liquid, and squeezing out potable water.
The researchers will now conduct further tests with populations in Myanmar via a charitable project sponsored by Singapore’s Lien Foundation.
The new material is described in Environmental Science and Technology this month.