Researchers at McGill University have discovered a new way to join materials together using ultrasound. Ultrasound – sound so high it cannot be heard – is normally used to smash particles apart in water. In a recent study, the team of researchers, led by McGill professor Jake Barralet, from the faculties of Dentistry and Medicine, found that if particles were coated with phosphate, they could instead bond together into strong agglomerates, about the size of grains of sand. Their results are published in the journal Advanced Materials.