Safe Water? Ask the Smartphone

Researchers combine an iPhone with optical filters to create a handheld analyzer for toxins, bacteria and other items of public health importance. Larry Greenemeier reports

Join Our Community of Science Lovers!

A virtual cottage industry has emerged around finding innovative uses for smartphones, well beyond basic calling, texting and Internet access. In particular, there’s been a lot of interest in turning iPhones into something like the Star Trek medical tricorder.

For example, University of Illinois researchers are developing an app and cradle-like device that makes the iPhone a biosensor. The key is the smartphone’s camera and processing power combined with the lenses and filters located in the cradle.

Just put a sample of what you want to study on a slide and insert it into the cradle. The iPhone screen indicates a shift in wavelength when the cradle’s photonic crystal detects toxins, proteins, bacteria, viruses or other biological materials on the slide. The researchers published in the journal Lab on a Chip. [Dustin Gallegos et al., Label-free biodetection using a smartphone]


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Imagine using a smartphone to tell if there are toxins in harvested corn and soybeans or pathogens in a water supply. That’s a handy tool that lowers the cost of medical fieldwork. Plus, when you’re done, it’s easy to call in the results.

—Larry Greenemeier

[The above text is a transcript of this podcast.]

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe