In an effort to help make world health outcomes more equitable, an Iowa high school student has developed organic, color-changing sutures that warn of infection as soon as it appears.
As a high school junior in October 2019, Dasia Taylor first took on the project as a science fair entry. “I read an article about how these scientists created these stitches that involved this really fancy technology that I perceived to be inequitable to those that would actually be able to need this technology,” she said in an interview with PBS.
Most of the “smart stitches” she read about required the use of smart technology, not always available in third-world countries. A Pew research poll in 2017 found that in Tanzania, for example, just 13 percent of the population owned smartphones. And while the numbers are higher in some African countries, the viability of smart sutures in that continent is minimal.
But infections are high. In low-and middle-income countries, 11 percent of all surgical wounds develop infections, according to the World Health Organization, compared to just four percent of all surgeries in the U.S.
Taylor, who graduated this past spring from high school, was particularly moved by how many African women suffer from infections after cesarean sections. In some nations, up to 20 percent of those who delivered by c-section develop potentially life-threatening infections.
Taylor subsequently tried to find a cheaper, more readily available solution to identifying wounds gone wrong. Since human skin is naturally acidic, with a pH of about five, she looked for natural indicators that could detect pH changes (when skin is infected, it can have a pH of up to 9). After learning that fruits and vegetables change color with pH level, she struck upon a feasible solution.
“I found that beets changed color at the perfect pH point,” Taylor told Smithsonian Magazine. “Bright red beet juice turns dark purple at a pH of nine. That’s perfect for an infected wound. And so, I was like, ‘Oh, okay. So beets is where it’s at.’”
She then tested various suture materials that would hold the beet juice dye and found that a cotton-polyester blend worked best.
Using artificial skin pads, Taylor sewed on her sutures and exposed them to different pH levels. When the stitches encountered a high pH, they changed from red to purple, making it clearly visible when alterations were happening at the surgical site. And if the site was free of infection, the sutures faded to gray after three days.
Kathryn Chu, the director of the Center for Global Surgery at Stellenbosch University in South Africa, praised Taylor for her efforts toward health equity. “I think it is amazing that this young high school scientist was inspired to work on a solution to address this problem,” she wrote in an email. “A product that could detect early [surgical site infections] would be extremely valuable.”
For her work, Taylor was named one of the top 40 finalist in the prestigious Regeneron Science Talent Search. Even as she prepares to attend the University of Iowa this fall, she is working on a patent for her beet-juice stitches.
Of course, concept isn’t perfect quite perfect yet, with sterilization being at the top of the issues to be solved. The cotton thread that accepts the beet dye effectively is also more prone to picking up infection-causing bacteria than standard surgical material.
Asked if she still counts her invention as a success, Taylor replied, “Yes, because it works. It does detect pH. It does change colors where it needs to change colors. There are just some details that need to be worked out, but they’re not insurmountable.”