Researchers at the Massachusetts Institute of Technology have developed a microchip that could one day allow the automated delivery of drugs such as insulin. In a recent issue of Nature (397 , 335–338, 1999), Robert Langer and his colleagues at MIT (Cambridge, MA) report the creation of a chip etched with reservoirs that can be loaded with liquid and "opened" using electrical current. Each reservoir is gated by a gold membrane that dissolves when an electrical current passes through it, allowing the controlled release of the reservoir contents. At their present size, microchips can accommodate approximately 1,000 such reservoirs. Langer believes that this technology could be coupled to a microprocessor and a battery to allow the timed administration of powerful drugs such as painkillers, chemotherapeutic agents, and fertility drugs over prolonged periods. "This could be a biocompatible, self-contained unit, possibly swallowable," he envisages. In addition to drug delivery, the microchips could also be used in fields such as medical diagnostics, chemical detection, and microbiology. As with any emerging technology, Langer is excited by the possibilities: "There are so many other applications, right now, it's hard to predict where it will end up."