Single-celled soccer on simple 'scope
Engineers have unveiled a cheap, open-source microscope that turns protozoa into Pac-Man.
Using 3D-printed parts and a smartphone, Stanford University’s ‘LudusScope’ allows kids to make serious observations with miniature light-seeking microbes called Euglena.
But because learning must be fun, LudusScope can convert the movements of the tiny lifeforms into fun and interactive video games.
“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 Ingmar Riedel-Kruse, an assistant professor of bioengineering.
“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.”
The LudusScope holds a microscope slide in which Euglena swim freely, surrounded by four LEDs.
Users can influence the direction hat these light-responsive microbes swim by using a joystick that activates the LEDs.
Above the platform, a smartphone is held in position so that its camera sits over a microscope eyepiece, providing a close-up view of the cells on its screen.
The accompanying smartphone app runs software overlays on top of the image of the cells.
One game is a version of Pac-Man, with a maze containing small white dots.
Kids can select one cell to track, then use the LED lights to control which direction the cell swims in an attempt to guide it around the maze and collect the dots.
Another game places the microbes in a soccer stadium and uses their orientation to judge where they would kick a ball, if they had legs or a ball.
But it is not all fun and games – other applications provide microscope scale-bars, real-time displays of swimming speed or zoomed-in views of individual cells for proper scientific study.
The idea is for students to be able to collect data on Euglena behaviour, swimming speed and natural biological variability, and to encourage teachers to have students model the behaviours they see using graphs and maps.
In its current iteration, a teacher who wanted to use LudasScope in class could start with the open-source 3D printing patterns and software, which are included in a paper on the device published in PLOS One.
While an increasing number of schools have 3D printers, those that do not can send the plans to a professional printer. Either way, they will receive pieces to construct the stage that holds a microscopic slide and a holder for the microscope eyepiece and smartphone.
For the joystick controller, students need to wire a small circuit out of common electronics parts to receive signals from the joystick and transmit them to the LEDs.
Euglena are common in science labs classrooms already, and can be purchased from biological supply companies. Some of the games require the Euglena to swim in a chamber made by adhering strips of double-sided tape to the slide and to the cover slip.
See the exciting device in action in the videos below.