a crab on beach

a crab on beach

A novel medical dressing aids in the healing of skin wounds. The structural substance found in the bones, scales, and shells of marine creatures and insects serves as its creative element. This polymer, known as chitin (KY-tin), is nature’s second most abundant substance after plant cellulose. And, being a byproduct of seafood processing, it is inexpensive. 

Healing Like Crabs

Jinping Zhou is a chemist at China’s Wuhan University. His team was aware that chitin may aid in the battle against pathogens and has been demonstrated to improve wound healing in some cases. These researchers wondered if using it to make gauze might expedite wound healing faster than standard cellulose-based gauze. 

To test this, they created dressings from various chitin-based fibers and tested them on rats. They examined the wounds under a microscope. The most delicate chitin gauze accelerated the development of new skin cells and blood vessels in healing. 

Treated wounds generated more muscular collagen fibers. Collagen, a protein, is the primary structural component of our bones, muscles, skin, and other bodily components. It aided in the strengthening and smoothing of the regrown skin during healing. Because chitin effectively fights germs, Zhou’s team believes the new bandage will reduce the risk of infection. In the January 2021 edition of ACS Applied Bio Materials, the researchers reported their novel chitin-based gauze. 

From shells to fibers

Chitin’s backbone is a string of molecules comprised of glucose, a simple sugar. Each of the glucose molecules in the string has been acetylated (Ah-SEE-Tyl-ay-tud). Each has a set of atoms consisting of one oxygen, two carbons, and three hydrogens (including the fourth hydrogen attached to the nitrogen.) Chitin is water-repellent due to the acetyl groups. By removing some of them, chitin becomes simpler to deal with for healing efforts. 

The researchers crushed up crab, shrimp, and lobster shells for their novel healing gauze. They immersed the gritty pieces in specific solvents for 12 hours. They converted the chitin-rich fluid into wet fibers by heating, bleaching, and other procedures. These chemical treatments have the potential to eliminate more than half of the acetyl groups. Zhou’s team next created fibers with varying levels of acetylated glucose. 

A unique machine spun the fibers into cloth. Fattening the cloth between two heated steel sheets gave it the appearance of gauze, which has long been used as a wound treatment or healing bandage. There is no need for weaving or sewing. 

The researchers employed 18 rats to see how much acetylation in the fiber’s chitin worked best. Each animal has four 1-centimeter-diameter (0.4-inch-diameter) circular wounds. They wrapped each one with a different chitin gauze. Researchers gave one set of rats regular cellulose gauze. They gave another group a slightly different type. The researchers assessed how much healing had happened every three days. 

Dressings produced from chitin and containing 71% acetylated glucose performed the best. This was notably evident on days three and six. After 12 days, the difference was more minor but still discernible.