Hydrogels 2 (IMAGE) University of Texas at Austin Caption Using the hydrogel tablet to purify water requires zero energy input and doesn’t create harmful byproducts. Credit The University of Texas at Austin Usage Restrictions None License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.