Soon, you may never have to play Russian roulette with potato salad again. Instead of just hoping that E. coli bacteria aren't present in your foods or drinks, you could instead use your mobile phone to find out for sure. That phone would have to be equipped with a bacteria-detecting scanner, which researchers from the UCLA Henry Samueli School of Engineering and Applied Science recently created - in a prototype version, for now.
The device attaches to the phone's camera and incorporates semiconducting quantum dots, combined with a grouping of glass capillary tubes that contain antibodies. When E. coli bacteria from liquid samples are placed within the scanner, they are captured on the capillary surface, where they get "excited" by the light from built-in LED bulbs.
This reaction causes the quantum dots to emit florescent light, which is magnified by a lens located beneath the capillaries, and then captured by the phone's camera - essentially, the device scanner serves as an inexpensive miniature florescent microscope. The specific concentration of E. coli is determined by quantifying the amount of light being emitted within each tube.
So far, there's no word on when or if a commercial version of the device might be available.
A paper on the research was recently published in the journal of The Royal Society of Chemistry.