BioFiber System for Self-Healing Concrete (IMAGE) Drexel University Caption SEM images of the BioFiber's core fiber with hydrogel coating. Credit Drexel University 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.