Nobody likes being jabbed with a needle. But how to deliver medications without pain? One solution: arrays of tiny silicon needles. Georgia Institute of Technology researchers Mark Prausnitz and Mark Allen fabricated a prototype array 10 millimeters square, bristling with silicon needles 150 microns long. Such needles make a microscopic hole in the skin's outer layer, which is devoid of nerve endings. Such devices could offer the convenience of skin patches but administer a much wider variety of drugs than the few (such as nicotine) that are absorbed directly through the skin.

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