A team of researchers at Duke University are using collapsible microscopic bubbles to shoot drugs directly through the walls of a cancer cell, according to New Scientist's Jamie Condliffe. When the bubbles collapse, they release a jet of medication so powerful that it can punch through cell walls. The researchers formed the bubbles by applying heat or ultrasound to a liquid — when the pulse is taken away, the bubbles burst, Condliffe says. The team struggled with the problem of controlling the direction and strength of the jet, but using specific laser wavelengths, the researchers were able to show that pairs of bubbles in close proximity collapse in a predictable pattern, which means they could be used as a targeted drug delivery system, Condliffe adds.