Stanford researchers develop low-cost paper microscope

A team of Stanford researchers has developed an ultra-low cost paper microscope that offers the potential for more effective disease diagnosis in developing regions.

According to Assistant Professor of Bioengineering Manu Prakash, the Foldscope was inspired by methods of mass production that Prakash witnessed while traveling in India and Thailand. Prakash subsequently applied that concept of scalability to meeting the challenges of diseases he had encountered in Africa.

Each Foldscope contains three stages — a specimen stage in which to place the slide, an optics stage that holds a ball lens and an illumination stage that contains an LED light.

To view the specimen sample, users place their eyebrow against the paper with their eye close to the lens, in a fashion similar to the use of a traditional microscope. Magnification and image panning are controlled by the user’s thumbs, including sliding to view different parts of the image and using a simple flexing mechanism to control magnification.

In late 2012, Prakash and his team received a $100,000 grant from the Grand Challenges Explorations, an initiative of the Bill & Melinda Gates Foundation, in order to field-test the microscope.

Jim Cybulski Ph.D. ‘14, a mechanical engineering doctoral student, was part of Prakash’s field team and has travelled to underdeveloped areas in Nigeria and India to investigate the microscope’s applications there.

“It’s really a different experience once you get outside the lab,” Cybulski said. ”You understand how people perceive it and how it fits into their daily life.”

According to Cybulski, field testing has revealed several concerns about using Foldscope, including eye strain, ergonomics and examining potentially infectious samples so close to one’s body.

As a result, the team is developing a different type of microscope for certain riskier circumstances. This specialized microscope will feature a projection system that allows for a magnified image to be projected against a wall.

In the same style of the original Foldscope, this microscope will still be financially feasible, with a target cost of about 10 dollars.

In the future, according to Cybulski and Prakash, Foldscopes will be designed so that each type of disease will have a correlating Foldscope meant exclusively for that disease, minimizing price and bypassing the difficult process of optimization seen with traditional multipurpose microscopes.

Prakash noted that the microscopes have two distinct but interrelated applications: use in education — by opening up microscopy to students — and in diagnostic healthcare in regions where microscopes may not be widely available.

Although the initial goal of the project was to help improve healthcare, Prakash argued that using Foldscopes for education has become integral to its development.

“We have a very simple goal that every single kid in the world should grow up with a microscope,” Prakash said. “We should all be carrying around microscopes in our pocket all the time.”

The team’s Ten Thousand Microscope Project tasks participants with helping to test Foldscopes in different situations around the world, forming a crowd-sourced knowledge bank. Approximately 8,000 people have already signed up, with nearly 25 nations represented.

Each recipient is asked to contribute a short report detailing a science experiment, exploration or other activity performed with the Foldscope in order to form a large “repository of curiosity,” as Prakash puts it. One of the participants reported convincing Mongolian farmers of the need to pasteurize their milk using Foldscope, and a young girl elsewhere used the paper microscope to examine dead bees in order to understand why they die.

Going forward, Cybulski cited fluorescence imaging, in which certain materials emit different colors of light than those shone on them, as a potential area of expansion. Meanwhile, Prakash hesitated to identify a specific future for Foldscope but emphasized the innovation’s broader implications.

“Microscopy is just a way to think about the world,” Prakash said. “It is very much is a window into the world, but what you do with it is very, very, very broad and it cannot be anticipated.”

 

Contact Skylar Cohen at skylark ‘at’ stanford ‘dot’ edu.