By Peter Weiss
Blurring the boundaries between biology and the realm of electromechanical machinery, technologists have already used components of the natural world such as DNA to make robots. They’ve also coaxed living nerve cells to grow on a microchip, allowing neuroscientists to eavesdrop on cell-to-cell signaling (SN: 10/6/01, p. 216: Available to subscribers at Nervy chip may open window into brain; 6/12/04, p. 382: Available to subscribers at DNA puts its best foot forward).
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Now, two chemical engineers have created an electromechanical device out of living microbes. Vikas Berry and Ravi F. Saraf of the University of Nebraska in Lincoln have converted bacteria into humidity sensors by studding the cells’ surfaces with gold nanoparticles.