A smartphone device able to detect toxic algae in minutes could help slow the spread of the harmful microorganisms.
The device created by the team at the National University of Singapore replaces expensive equipment and the need for skilled operators with a simple and portable option.
The system relies on a microfluidic chip coated with a photoconductive polymer that guides water droplets during the analysis process. The chip is placed on the smartphone’s screen, where the change in voltage created by the light and dark areas alters the water droplets’ surface tension. As the water droplets move toward the dark areas, they mix with a chemical that stains any present algae cells—allowing the images of the cells to be captured by the smartphone camera and analyzed by a companion app. The system can identify and count the four types of toxic algae, with the results delivered in just fifteen minutes.