Sports apparel made from synthetic materials that wick away moisture and prevent the proliferation of odour-causing bacteria are all well and good, but researchers at the MIT had just taken workout clothing to the 21st century with a brand-new suit and pair of shoes that contain flaps lined with microbial cells which act as sensors and actuators, driving the flaps to open and close in response to body heat and moisture.
Details of both designs had been published in the journal Science Advances.
The reasons for using live cells are numerous: they are easy and inexpensive to produce in vast quantities, require no additional elements to carry out their task, can be programmed to implement other functions (such as fluorescence) through genetic engineering, and are safe to touch and even ingest.
First, the researchers covered several layers of latex with a common, non-pathogenic strain of E. coli and subjected it to changing moisture conditions. Once placed on a hot plate to dry, the cells began to shrink, causing the overlaying latex layer to curl up. When the fabric was exposed to steam, the cells expanded, causing the latex to flatten out again.
With their first success under the belt, the researchers then fashioned the biofabric into a wearable suit with a pattern of cell-lined flaps, strategically positioned in spots 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,” said Lining Yao of MIT. “We redesigned the garment using a fusion of heat and sweat maps to, for example, make flaps bigger where the body generates more heat.”
The inner cell layer of the fabric has a support frame that prevents it from directly touching the skin, allowing the cells to react to changes in moisture level of the air right above it.
Preliminary tests showed that participants who wore the suit had lower body temperature and less sweat on their skin, as compared to participants who donned suits with non-functioning flaps.
The researchers also designed a prototype of shoes, also lined with flaps in accordance with heat and sweat maps of the foot.
In the future, the team plans to collaborate with sportswear companies, and look into other uses, such as moisture-responsive curtains, lampshades, and bed sheets.