Microscopic submarines for your stomach

Tiny ‘submarines’ that speed independently through the stomach, use gastric acid for fuel (while rapidly neutralizing it), and release their cargo precisely at the desired pH: Though it may sound like science fiction, this is a new method for treating stomach diseases with acid-sensitive drugs. The technique is based on proton-driven micromotors with a pH-dependent polymer coating that can be loaded with drugs.

(via WSJ)