With spiderwebs as their guide, scientists at the Massachusetts Institute of Technology developed a new kind of double-sided tape that works in wet environments. The tape is designed to stick body tissue together after surgery and was inspired by the way spiderwebs catch spider’s prey in the rain.
Researchers had noticed spiderwebs contained charged polysaccharides, secretion that instantly absorbed moisture from the bugs that land in their trap, creating a dry spot to stick to. The double-sided tape does the same, and when tested on pig skin and lungs, it worked within seconds.
The research is published in the journal Nature.
Slippery Situations
Bandages slip off when you wash your hands, get in the shower, or anything that involves getting wet. That’s because sticky stuff usually doesn’t work when it’s wet, which is often an issue arising in a lot of industries, from construction to cosmetics. However, stickiness that lasts a long time is particularly essential when closing wounds during surgery on internal organs. It’s challenging to get tissues in the body to form a tight seal because moisture on their surface makes them very slippery.
Sutures can sometimes cause pain or infections, and tissue glues can take too long to work and could drip on to other body parts. Therefore, this new sticky tape is a good option.
The Double-Sided Tape
To mimic the way the spiders catch their prey, the scientists developed a material that absorbs the water from tissues before quickly creating a bond. They used a polyacrylic acid, an absorbent material found in disposable baby diapers, to absorb moisture. The polyacrylic acid sucks up the water and develops weak hydrogen bonds, which temporarily holds the tissue together. Then, within five seconds, a class of chemicals called N-Hydroxysuccinimide (NHS) esters, fixed in the polyacrylic acid, takes control and forms even stronger covalent bonds with proteins in the tissue.
Additionally, the bandage can be reinforced with gelatin, which breaks down in days or weeks; or chitosan, a polysaccharide from insect shells that lasts one to twelve months.
Lead study author, Xuanhe Zhao, from MIT, said:
There are over 230 million major surgeries all around the world per year, and many of them require sutures to close the wound, which can actually cause stress on the tissues and can cause infections, pain, and scars. We are proposing a fundamentally different approach to sealing tissue.
Testing On Animals
The researchers have not tested this new material on humans yet, but they have already tested it out on different parts of rat and pig tissue. The team successfully used it to repair small intestines, stomach, skin, and liver tissue. “It’s very challenging to suture soft or fragile tissues such as the lung and trachea, but with our double-sided tape, within five seconds, we can easily seal them,” said one of the authors of the study, Hyunwoo Yuk.
Future Plans
The double-sided tape could be used to implant medical devices to organs, such as the liver or heart, but without causing damage or puncturing tissue. Now, the scientists plan to continue making tests on animals to perfect the tape and hopefully begin trials on humans.
