Scientists Publish Blueprints for Cheaper Single-Molecule Microscope

JOEL WILLIAMS, ASSOCIATE EDITOR
joel.williams@photonics.com

A team from the University of Sheffield has designed and built a single-molecule microscope for one-tenth the cost of commercially available models — and shared the build instructions to make the equipment more readily available.

The microscope, called the smfBox, is able to image at single-molecule resolutions. Because the high cost of equipment and components restricts access to microscopes with such resolution, the smfBox project aims to increase access to single-molecule microscopy; the microscope can be built for £40,000, compared to the £400,000 price tag on many commercial models.

The smfBox can be built from readily available parts for a tenth of the cost of commercially available single-molecule microscopes. Courtesy of Timothy Craggs, University of Sheffield.

The work stems from professor of chemistry Timothy Craggs’ need for such a device.

“When I started my lab at the University of Sheffield, I needed an instrument to do single-molecule Forster Resonance Energy Transfer (smFRET) experiments, but even a generous startup package (by U.K. standards) was not sufficient to buy an off-the-shelf instrument,” Craggs told Photonics Media. “We set about building something with an emphasis on simplicity of design, ease of use, and, crucially, as low cost as possible.”

The microscope, he said, is built from readily available parts, and the team acquired certain key components, such as lasers and detectors, from specialist suppliers. The main body of the microscope is made of machined aluminum, the CAD files for which are included in the work.

The microscope is designed in such a way that it can be used with little training, and the lasers have been shielded in such a way that it can be used in normal lighting.

“We wanted to democratize single-use molecule measurements to make this method available for many labs, not just a few labs throughout the world,” Craggs said. “This work takes what was a very expensive, specialist piece of kit, and gives every lab the blueprint and software to build it for themselves, at a fraction of the cost.”

Craggs noted that many COVID-19 tests work at the single-molecule level, underscoring the importance of the technology being readily available.

“This instrument is a good starting point for further development toward new medical diagnostics,” he said.

The Craggs Lab has so far used its smfBox to investigate fundamental biological processes such as DNA damage detection, the study of which could lead to better therapies for diseases, including cancer.

“I know already that many early career researchers looking to start their own labs are really excited about building this instrument, as it is so much more economical than buying a commercial version,” Craggs said. “I have spoken to quite a few people at conferences who were going into faculty position interviews with the blueprints and costs of the smfBox in their hands, as a good way to get their single-molecule labs up and running.

“Ultimately, though, I hope this is the first step to bring these types of measurements to less specialized users and labs, so that many more people have access to the power of single-molecule measurements.”

The work was published in Nature Communications (www.doi.org/10.1038/s41467-020-19468-4).