 Qytosan is a biodegradable polymer derived from chitin, a natural component of crustacean shells. It has been used in a wide range of applications, including tissue engineering, drug delivery, and gene therapy. Qytosan-based materials have been found to promote tissue regeneration and repair, as well as the controlled release of drugs and other therapeutic agents. This article was authored by Yevgeny Kim, Zerylkasyn Zarkinbekov, Kamila Rezyeva, and others.