Suzanne's Mom's Blog

These are things I already knew about beets: girls of my mother’s generation used a cut beet to color their cheeks; boiling beets makes a good egg dye. Today I learned from a teenager that beets’ can detect infection.

Theresa Machemer reported at Smithsonian, “Dasia Taylor has juiced about three dozen beets in the last 18 months. The root vegetables, she’s found, provide the perfect dye for her invention: suture thread that changes color, from bright red to dark purple, when a surgical wound becomes infected.

“The 17-year-old student at Iowa City West High School in Iowa City, Iowa, began working on the project in October 2019, after her chemistry teacher shared information about state-wide science fairs with the class. … This January, Taylor was named one of 40 finalists in the Regeneron Science Talent Search, the country’s oldest and most prestigious science and math competition for high school seniors.

“As any science fair veteran knows, at the core of a successful project is a problem in need of solving. Taylor had read about sutures coated with a conductive material that can sense the status of a wound by changes in electrical resistance, and relay that information to the smartphones or computers of patients and doctors. While these ‘smart’ sutures could help in the United States, the expensive tool might be less applicable to people in developing countries. … On average, 11 percent of surgical wounds develop an infection in low- and middle-income countries, according to the World Health Organization, compared to between 2 and 4 percent of surgeries in the U.S.

“Infections after Cesarean sections particularly caught Taylor’s attention. In some African nations, up to 20 percent of women who give birth by C-section then develop surgical site infections. Research has also shown that health centers in Sierra Leone, the Democratic Republic of the Congo and Burundi have similar or lower rates of infection, at between 2 and 10 percent, following C-sections than the U.S., where rates range from 8 to 10 percent. But smartphone access is markedly different. …

“ ‘I’ve done a lot of racial equity work in my community, I’ve been a guest speaker at several conferences,’ says Taylor. ‘So when I was presented with this opportunity to do research, I couldn’t help but go at it with an equity lens.’ …

“Healthy human skin is naturally acidic, with a pH around five. But when a wound becomes infected, its pH goes up to about nine. Changes in pH can be detected without electronics; many fruits and vegetables are natural indicators that change color at different pH levels.

‘I found that beets changed color at the perfect pH point,’ says Taylor. 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.” ‘

“Next, Taylor had to find a suture thread that would hold onto the dye. She tested ten different materials, including standard suture thread, for how well they picked up and held the dye, whether the dye changed color when its pH changed, and how their thickness compared to standard suture thread. After her school transitioned to remote learning, she could spend four or five hours in the lab on an asynchronous lesson day, running experiments. A cotton-polyester blend checked all the boxes. …

“Kathryn Chu, the director of the Center for Global Surgery at Stellenbosch University in South Africa, focuses on improving equitable access to surgical care. ‘I think it is amazing that this young high school scientist was inspired to work on a solution to address this problem,’ the surgeon writes in an email. ‘A product that could detect early [surgical site infections] would be extremely valuable. However,’ she adds, ‘how this concept could translate from the bench to the bedside needs further testing.’ …

“The same non-absorbency that makes standard suture thread hard to dye with beet juice also keeps bacteria out, and vice versa. While cotton thread’s braided structure gives it the ability to pick up the beet dye, it also provides a hiding place for bacteria that cause infections.

“Taylor has been pursuing a line of research since the beginning of her project that might counteract the risks posed by using cotton.”

More at Smithsonian, here. Also at the Washington Post, here.

Photo: Nick Collins via Unsplash