An affordable tracking microscope to democratize microorganism research

Studying the complex motility patterns of cells and microorganisms is essential to understanding their behavior and biomechanics. However, many conventional microscopes are limited by fixed objectives and the inability to follow organisms over long periods without manual intervention.

But researchers at the Georgia Institute of Technology have overcome these limitations by developing a self-contained, modular, inexpensive tracking microscope that is easy to assemble.

Priced at $400 in parts with do-it-yourself assembly instructions available, Trackoscope is a frugal scientific innovation accessible to a wide range of users, from high school labs to resource-constrained research environments.

Developed in the lab of Saad Bhamla, an associate professor in Georgia Tech’s School of Chemical and Biomolecular Engineering (ChBE), the Trackoscope is described in a new paper published in the journal PLOS ONE

The paper’s lead author is Priya Soneji, a mechanical engineering student and undergraduate researcher working in the Bhamla lab. Now a senior at Georgia Tech, she came up with the idea for the Trackoscope in 2019 while she was still a student at Milton High School near Atlanta.

“I was frustrated with having to keep moving around on the slide to view the organisms under the microscope, and I thought there might be a way to automate this since I had been working with robotics since third grade,” Soneji said.

She then heard about the wide range of frugal scientific innovations coming out of Bhamla’s lab and so reached out to him to start the project while she was finishing high school. “I pitched it to him and he was immediately on board.”

Besides Bhamla, Soneji’s research mentors include paper co-author Elio Challita (Bioengineering Ph.D. 2023), who is now a postdoctoral researcher at Harvard University.

Capturing diverse behaviors

Soneji’s original concept has evolved into a versatile microscope capable of monitoring organisms at speeds ranging from 0.1 µm/s to 2 mm/s in a large tracking area of ​​325 cm²This extended view minimizes the risk of organisms colliding with the container walls, thus preserving their natural behaviors and enabling experiments involving predator-prey dynamics.

“Using Trackoscope, we captured a wide range of behaviors, from air-water swimming locomotion in amoeba to bacterial hunting dynamics in Actinosphaerium, gait in Tardigrada, and binary fission in mobile blepharitis,” Challita said.

“With Trackoscope, any scientist will be able to acquire new knowledge about the microbial world.”

Frugal scientific solution

Compared to the $400 Trackoscope, existing tracking solutions can cost between $1,000 and $5,000, putting them out of reach for researchers in resource-limited environments.

The Trackoscope’s modular design makes it easy to customize and adapt to specific research needs. Its construction involves simple assembly using materials such as wood or acrylic, as well as laser-cut and 3D-printed components.

“We want to make it easy for labs to build this and use it,” Soneji said.

The Trackoscope optical module includes key components such as a high-quality Raspberry Pi camera with a 12.3MP Sony IMX477 sensor and an achromatic doublet lens. This configuration enables a versatile range of magnifications from 20X to 200X, allowing precise observation of microorganisms at different speeds.

Trackoscope uses motorized XY stage controls, but researchers have developed prototypes with improved control mechanisms, such as motorized Z-axis adjustments.

“These innovations highlight Trackoscope’s adaptability and its potential for future improvements in microorganism research and STEM education,” Bhamla said.