Humble sea squirt could inspire new gold rush


In South Korea, scientists have developed a material based on chitin and gallic acid that mines gold from sea water. Inspired by tunichromes—materials sea squirts and other filter feeders use to remove food particles from sea water—the Pohang University of Science and Technology scientists say the material collected 99% liquefied gold while filtering out the hazardous material chrome.

Tunichrome has long been of interest, but exists in only small amounts in the sea squirt’s blood. Chitin, on the other hand, is an abundant material found in crustaceans such as shrimp and crabs.

The new material can replace toxic ones currently used to collect metals from seawater. POSTECH’s work was recently published ACS Applied Materials & Interfaces journal.