Microbial cells drive the development of sportswear with changes in humidity

American researchers have developed a breathable training sportswear that can be contracted and expanded in response to changes in humidity through a breathable flap that is lined with living microbial cells to maintain the wearer's coolness and dryness.

According to a team of scientists at the Massachusetts Institute of Technology (MIT), these microbial cells act as tiny sensors and actuators that drive the lid open when the athlete sweats and close when the body cools.

In nature, biologists have observed that when humidity changes, organisms and their components (from pineal scales to microbial cells, even specific proteins) can change their structure or volume. The MIT team predicts that natural body transformers such as yeast, bacteria, and other microbial cells may be used to make components that respond to humidity.

The researchers first studied the most common non-pathogenic strains of E. coli and found that they would expand and contract with changes in humidity. The cells were then designed to visualize green fluorescent proteins, allow cells to feel wet under conditions of light, and print E. coli onto rough natural emulsion film using cell printing methods.

The bio-cloth is then made into a wearable garment, wherein the lining latex bag cover is patterned on the back side, and each bag cover is positionally adjusted according to the degree of opening thereof and according to the preset distribution of heat and sweat generated by the body. .

Former graduate student Lining Yao collaborated with former MIT Media Lab and chemical engineering research scientist Wen Wang to implement the project, and called the project bioLoic. Lining Yao said: "People may think that heat and sweat are the same, but in fact Areas such as the lower sacral vertebrae that produce a lot of sweat do not produce much heat. We redesigned the garments using the positional distribution of heat and sweat. For example, the part of the body that produces more heat, the more the flap Big".

The support frame under each flap allows the inner cell layer of the fabric to not directly contact the skin, while the cells can feel and respond to changes in humidity in the air on the skin. In the test of running suits, the study participants wore the ready-to-wear and used treadmills and bicycles to exercise, while the researchers used small sensors on their backs to monitor their temperature and humidity.

After 5 minutes of exercise, the cover of the sportswear began to open when the participants felt hot and sweaty. According to the sensor data, the flap can effectively remove sweat from the body and lower the skin temperature, which can better eliminate sweat and cool down when wearing a running suit with a similar functional bag.

Researchers say that water-sensitive cells do not require additional elements to sense and respond to humidity. The microbial cells they use have proven to be safe to touch or even consume. In addition, the research team said that with the new genetic engineering tools now available, cells can be prepared quickly and in large quantities to perform multiple functions besides responding to moisture.

To demonstrate this last point, the researchers designed and created water-sensitive cells that not only open the flap, but also glow in wet conditions.

Wen Wang added: "We can combine our cells with genetic tools to introduce other functions into these living cells. We use fluorescent light as an example. When you run at night (in the dark), others will see it. In the future we can By combining genetic engineering with odor release, it is possible that the shirt will give off a good smell after fitness."

At the same time, the researchers also integrated the humidity-responsive fabric into the initial shape of the running shoes. The inner layer has a similar cell-lined flap for gas to escape and absorb moisture.

Where the sole of the foot contacts the sole, the researcher stitches a plurality of downwardly curved flaps with the cell lining layer facing but not touching the runner's foot. The researcher also designed the size and position of the flap based on the hot air and sweat position of the foot.

Wen Wang explained: "In the beginning, our idea was to put the flap on the top of the shoe, but we found that in general, the back of the human body does not sweat, but the sole of the foot will sweat a lot, which will lead to something like this. The disease. So we are wondering, is it possible to keep the feet dry and avoid these diseases?"

Just like sportswear, when a researcher increases the humidity in the environment and dims or turns off the light under dry conditions, the flap on the running shoe opens and shines.

Looking ahead, the R&D team hopes to work with sportswear companies to commercialize their designs.

Xuanhe Zhao, associate professor and co-author of Robert N. Noyce's Department of Mechanical Engineering, said: "This research is an example of using biology to design new materials and equipment and to achieve new functions. We believe this new field is alive. Materials and equipment will find important applications between engineering and biological systems interactions."