Researchers from UCLA have designed a 3D-printed smartphone attachment and app that can detect the presence of mercury in water. The inexpensive and lightweight “lab on a phone” makes chemical testing more widely available, reducing both the time and cost.
The accompanying app lets people plot the resulting concentration levels to create a crowdsourced map. The test for mercury can be performed easily by anyone after only minimal training.
First, a sample of water is collected in a disposable test tube and then held up to a smartphone equipped with the optical attachment. Using the attachment’s LEDs, which are set to two specific frequencies, it detects subtle changes in how light is transmitted to the phone’s built-in camera due to mercury-induced nanoparticle clustering in the water. Aydogan Ozcan, the principal investigator on the research, said:
Our new platform for mercury testing is essentially a lab on a phone. It’s portable, lightweight and inexpensive to manufacture. And, because of the global proliferation of mobile devices, it could make testing for mercury widely available. Having this kind of test available in resource-limited areas and in the field was an important motivation for our work.