That modern gym clothing is breathable goes without saying. However, a new heat-regulating fabric developed by MIT researchers will probably change how you view sportswear design forever. Their newly announced “biofabric” is embedded with microbial cells that automatically open flaps when they sense heat and sweat – the whole high-tech idea being, you get to stay cool while cranking up some steam.
The new “biofabric” developed by a team of MIT researchers sounds like science fiction, but it’s true. As unbelievable as it sounds, their latest design – a breathable workout suit – incorporates ventilating flaps that automatically open and close in response to one’s body heat and sweat. These small flaps, varying from thumbnail to finger in size, are each lined with live microbial cells that naturally shrink and expand in response to changes in humidity. In effect, the cells act as tiny sensors and actuators – driving the flaps to open when an athlete works up a sweat, then pulling them closed when the body cools down again.
And, to prove they really knew what they were doing, the team engineered the cells to glow in the dark, too. “We can combine our cells with genetic tools to introduce other functionalities into these living cells,” explains Wen Wang, the paper’s lead author and former research scientist in MIT’s Media Lab and Department of Chemical Engineering. “We used fluorescence as an example, as this can let people know you are running in the dark. In the future we can combine odour-releasing functionalities through genetic engineering. So maybe after going to the gym, your shirt can release a nice-smelling odour.”
How the biofabric came about
Biologists have known for a long time that many living things, from pine cone scales to microbial cells and even some proteins, alter their structures or volumes when the humidity changes. This got the MIT team thinking. They suspected natural shape-shifters like yeast, bacteria, and other microbial cells could work as building blocks for the construction of moisture-responsive fabrics. “These cells are so strong that they can induce bending of the substrate they are coated on,” points out Wang.
To test their hypothesis, researchers started working with the most common non-pathogenic strain of E. coli. They then engineered the cells to express green fluorescent protein – enabling them to glow when sensing humidity. Finally, they used a cell-printing method (they’d developed previously) to print the modified E. coli onto sheets of latex. Once done, they worked the new biofabric into a wearable garment – designing a running suit with cell-lined latex flaps patterned across the suit’s back. They tailored the size of each flap, as well as the degree to which each one opens, based on where the body produces the most heat and sweat.
“People may think heat and sweat are the same, but in fact, some areas like the lower spine produce lots of sweat but not much heat,” says Lining Yao, co-lead author of the study. “We redesigned the garment using a fusion of heat and sweat maps to, for example, make flaps bigger where the body generates more heat.”
During trials, study participants donned the garment and worked out on treadmills and bicycles, while researchers monitored their temperature and humidity using small sensors positioned across their backs. After five minutes of exercise, the suit’s flaps started opening up, right around the time when participants reported feeling warm and sweaty. According to sensor readings, the flaps effectively removed sweat from the body and lowered skin temperature. When Wang tried on the suit herself, she got a pleasant surprise. After pedalling hard for a few minutes, she recalls: “it felt like I was wearing an air conditioner on my back.”
Going forward, the team’s looking to collaborate with sportswear companies to commercialize their designs. They’re also exploring other uses, including moisture-responsive curtains, lampshades, and bedsheets. – (c) 2017 NavWorld