Robert Pal/Durham University

Nanomachines drill holes into cancer cells

Someday doctors may use nanomachines to puncture cancer cells. The new machines are so tiny, at just a nanometer wide, that 50,000 of them could be lined up across the width of a human hair. Although the nanodrillers bear no physical resemblance to a machine we would recognize, the molecules strung together by chemists run like an electric motor. A stationary stator holds the machine in place while a moving rotor spins and drills across the cell membrane. The paddlelike rotor, a series of three rings of carbon atoms, begins rotating 2 million to 3 million times per second when hit by ultraviolet light. On either side of the stator are arms of carbon, nitrogen, and oxygen that stretch out and grip the surface of the cell. When scientists unleashed the nanomachines on human kidney cells in a dish, holes formed in the cells within a minute, and death soon followed. Molecules added to the stator’s arms can work as chemical zip codes to selectively direct the nanomachines to a particular structure on a cell’s surface, such as a protein expressed on prostate cancer cells. With this specific application, nanomachines in a dish targeted, punctured (causing them to leak contents and bubble up, as pictured), and killed prostate cancer cells more rapidly than neighboring hamster and mouse cells, the team reports today in Nature. Up next, the scientists plan to test their machines in microorganisms and fish.