Silklab is developing underwater adhesives for shark tagging and small drones for identifying Covid-19 in the environment
Eli Chavez
A lab in the Department of Biomedical Engineering at Tufts University is innovating with the help of one of the oldest and most domesticated animals on the planet: silkworms.
The Silklab at Tufts sounds more straightforward than it is. While the lab works with silk — a material humans have been using for over 5,000 years — new applications the Tufts lab has discovered feel virtually limitless.
The lab takes silkworm cocoons, extracts the worm and boils the cocoons in water with some salt. Once the cocoons unravel, the lab dissolves the silk in lithium bromide to create a solution of fibroin, one of the two proteins that make up silk. The lab can use the solution to pour into plastic molds, mix with ink, or be used with electronic sensors.
The innovation begins with the fibroin solution extracted from the silk cocoons. Currently, the silk lab is developing various projects with silk, from traditional clothing to medical implants and women’s health. The lab is integrating silk into patches that can monitor and analyze sweat to monitor health, as well as medical inserts to be used in surgery and designed to dissolve in the body.
Beyond clothing and medical devices, Silklab is also developing underwater adhesives for shark tagging and small drones that can detect if there is Covid-19 in the environment.
The Silklab isn’t the only one looking into the possibilities of the ancient thread. The lab has spun out startups like Framingham-based Sofregen, which uses silk to repair damaged vocal cords, and Cambridge-based Vaxess, which uses microneedles developed from silk for vaccine delivery. There are also startups like Silk Inc., a developer of nontoxic skin-care products, and Cocoon Biotech Inc., which develops dermatology products.
Part of the reason silk can be used for such a wide variety of purposes is that silk can stabilize molecules that would otherwise need to be refrigerated or stored in a liquid state, according to Fiorenzo Omenetto, the director of the Silklab and, if his door sign is to be believed, “Silk Lord.”
“Silk stabilizes a molecule that otherwise would need to be refrigerated or otherwise would have to be stored in a liquid state,” Omenetto said. “So you put it in a format you can print, shape and sculpt. That’s the material magic.”
Even though silkworm cocoons are small, a little goes a long way in the Tufts Silklab. Each cocoon weighs about one gram, which can be used for various projects, depending on how the lab uses it. For instance, if the lab uses the fibroin solution to mix with ink or for sensors, one cocoon can produce roughly 1,000 sensors, according to Omenetto.
Italian silk scraps for R&D
Distilling a fibroin solution from silkworm cocoons can also be time-consuming, taking as many as five days to create one bottle of solution for the lab to use. Luckily, the Silklab has ways around its bottleneck.
The lab has a commercial partner that provides them with silk powder and receives shipments of silk scraps from Italy that would otherwise be dumped. The silk powder and the scraps can be used to develop the same fibroin solution as the cocoons, reducing time and material costs.
With the many solutions silk makes possible, it can be hard to know where to focus. Omenetto likened the possibilities of silk to having the “most incredible Lego set” and being told to build whatever you want.
“I think that the directions we pick are the most surprising, which means that they open up something fundamental, something that you’ve never seen on the surface before, versus something that could have a high impact, like early detection of breast cancer,” Omenetto said. “So you pick through experience… I think it’s nice to connect the unconnectable, so there’s maybe the magic of trying to bring what was biological into the technical world.”