New York: Researchers at Stanford University have developed a smartphone microscope that allows kids to play games or make more serious observations with miniature light-seeking microbes called Euglena.

"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, 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," Riedel-Kruse noted.

Riedel-Kruse named his device the LudusScope after the Latin word "Ludus," which means "play," "game" or "elementary school". 

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.

On the phone, children can run a variety of software that overlay on top of the image of the cells. 

One looks like the 1980s video game 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 looks like a soccer stadium. 

Kids earn points by guiding the Euglena through the goal posts.

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 behaviour, swimming speed and natural biological variability. 

The details of the LudusScope were published in the journal PLOS ONE.