Self-Healing Hydrogels (image) Wyss Institute for Biologically Inspired Engineering at Harvard Share Print E-Mail Caption The team used ultrasound to trigger the alginate hydrogel (right) to release the blue-colored chemotherapy drug in high-dose pulses, as indicated by the newly blue color of the surrounding medium. (Drug release by diffusion alone takes much longer and would be less visible.) Credit Harvard's Wyss Institute and Harvard SEAS Usage Restrictions Credit: Harvard's Wyss Institute and Harvard SEAS Share Print E-Mail 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.