Researchers from the University of California San Diego have created an innovative display similar to a neon sign, that is composed of millions of bacterial cells. Thousands of fluorescent E. coli bacteria make up one biopixel on the living display, which can then be made to glow in unison.
A fluorescent protein was attached to the biological clocks of the bacteria within a colony, which synchronized them so they glowed on and off together like blinking light bulbs. Using this same technique, the team created a bacterial sensor capable of detecting arsenic, which made the cells blink on and off to indicate the presence of the toxin. They believe that low-cost biosensors could be designed to respond to changes in the quantities of different toxins over time. Jeff Hasty, professor of biology and bioengineering at UC San Diego, said:
These kinds of living sensors are intriguing as they can serve to continuously monitor a given sample over long periods of time, whereas most detection kits are used for a one-time measurement. Because the bacteria respond in different ways to different concentrations by varying the frequency of their blinking pattern, they can provide a continual update on how dangerous a toxin or pathogen is at any one time.
Check out this video of the biopixel display in action: