A toy, 3-D printed at Stanford, to look at microbes with smartphone

Stanford University researchers have built a microscope that uses 3-D printed parts and a smartphone to allow kids to play games or observe light-seeking microbes called Euglena.

The device, known as the LudusScope, is named after the Latin word "Ludus," which means play, game or elementary school, by Ingmar Riedel-Kruse, an assistant professor of bioengineering at Stanford, who has worked with graduate student Honesty Kim on the project.

"Many subject areas like engineering or programming have neat toys that get kids into it, but microbiology does not have that to the same degree," said Riedel-Kruse. "The initial idea for this project was to play games with living cells on your phone. And then it developed much beyond that to enable self-driven inquiry, measurement and building your own instrument."

Initially as part of a bioengineering class Riedel-Kruse taught, the LudusScope consists of a platform for the microscope slide where the Euglena swim freely, surrounded by four LEDs. Kids can influence the swimming direction of these light-responsive microbes with a joystick that activates the LEDs. Above the platform, a smartphone holder positions the phone's camera over a microscope eyepiece, providing a view of the cells below.

In a paper published in PLOS ONE on Wednesday, the researchers provided open-source 3D printing patterns and software for the device. A teacher who wanted to use it in class could start with producing pieces to construct the stage that holds a microscopic slide and a holder for the microscope eyepiece and smartphone. For the joystick controller, students would need to wire a small circuit out of common electronics parts to receive signals from the joystick and transmit them to the LEDs.

On the phone, children can run a variety of software that overlay on top of the image of the cells. Other non-game applications provide microscope scale-bars, real-time displays of swimming speed or zoomed-in views of individual cells. These let kids collect data on Euglena behavior, swimming speed and natural biological variability.

While continuing to update the LudusScope with input from teachers and students, Riedel-Kruse has received a seed grant to collaborate with an educational game company to carry out more user studies and to develop a science kit, according to a news release from Stanford. He expects that kit could be available for purchase in over a year. Endit