Researchers at the University of Illinois, Urbana-Champaign have developed a special cradle and app for iPhones. The cradle secures the alignment of several lenses to a photonic crystal that filters light at specific wavelengths that can be measured by the phone’s built-in camera. When a biological material attaches to the crystal – such as proteins, DNA or microbes – the reflected color will shift from a short wavelength to a longer one.
Normal microscopic slides can be coated with any biologic material of interest and primed to react to specific target molecules. After exposure to the test sample, the spectrum is re-measured. The degree of shift in the reflected wavelength is a measurement for the amount of target molecules in the sample. This analysis takes only a few minutes and can be used for screening of environmental samples or diagnostic tests in the field. The collected data can be geotagged and processed immediately for further analysis anywhere in the world.
Professor of electrical and computer engineering, Brian Cunningham, quoted in the press release:
“We’re interested in biodetection that needs to be performed outside of the laboratory. Smartphones are making a big impact on our society – the way we get our information, the way we communicate. And they have really powerful computing capability and imaging. A lot of medical conditions might be monitored very inexpensively and non-invasively using mobile platforms like phones. They can detect molecular things, like pathogens, disease biomarkers or DNA, things that are currently only done in big diagnostic labs with lots of expense and large volumes of blood. It’s our goal to expand the range of biological experiments that can be performed with a phone and its camera being used as a spectrometer. In our first paper, we showed the ability to use a photonic crystal biosensor, but in our NSF grant, we’re creating a multi-mode biosensor. We’ll use the phone and one cradle to perform four of the most widely used biosensing assays that are available.”
The researchers describe their technology this week in Lab on a Chip and the team is working to improve the manufacturing process for the iPhone cradle and planning a cradle for Android phones in the future as well. They expect the cradles to be available for purchase next year.
Publication in Lab on a Chip: Label-free biodetection using a smartphone
Press release: Cradle turns smartphone into handheld biosensor…